Timesheet Decimal Converter: H:MM to Decimal and Decimal to H:MM, Law Firm Billing Tenths, Consulting Quarter-Hour, Batch Invoice Total
The only timesheet decimal converter that works in both directions. Convert H:MM to decimal for payroll software, OR enter a decimal and get back the exact hours and minutes. Batch mode handles up to 6 billing entries with descriptions and calculates your total invoice amount at 0.1-hour (6-minute) billing increments used by law firms. 0.1h = 6 minutes. 0.25h = 15 minutes. 2.75h = 2h 45m. Free PDF billing summary.
Timesheet Decimal Converter
Convert up to 6 time entries with billing total
| # | Description (optional) | H:MM | ||
|---|---|---|---|---|
| 1 | h | |||
| 2 | h | |||
| 3 | h | |||
| 4 | h | |||
| 5 | h | |||
| 6 | h | |||
0.1h billing: each entry rounded UP to nearest 6 minutes. Used by law firms and most professional services billing. 0.25h billing: use our Minutes to Decimals converter for quarter-hour rounding.
Billing Entries Breakdown
Why Timesheet Decimal Conversion Works in Both Directions
Most time conversion tools only go one way: you enter hours and minutes and get a decimal. But professional timekeeping frequently requires the reverse. A client invoice arrives showing 2.3 hours billed. How long is that in hours and minutes? It is 2 hours 18 minutes. A payroll export shows 37.75 hours worked. What does that look like in H:MM format? It is 37 hours 45 minutes. A billing software entry of 0.7 hours: that is 42 minutes.
The ability to go from decimal back to H:MM is the difference between auditing your own time records and just accepting whatever a billing system outputs. This calculator handles both directions in one place, including a batch mode for up to 6 billing entries with running totals and invoice amounts.
How This Bidirectional Timesheet Decimal Converter Works
The H:MM to Decimal tab takes up to 6 time entries, each with an optional description. Enter hours and minutes for each billing matter, add your hourly rate, and get the exact decimal for each entry plus the total. Each entry is also shown rounded up to the nearest 0.1 hour (6 minutes), the standard law firm billing increment. The invoice total uses the rounded figures, matching how professional billing software calculates fees.
The Decimal to H:MM tab works in reverse. Enter any decimal value (such as 2.75 or 1.3333) and get back the exact H:MM equivalent (2h 45m or 1h 20m), total minutes, and rounded values at both 0.1-hour and 0.25-hour increments. Add a billing rate to see the difference between exact pay and rounded billing pay, useful for comparing billing methods.
The Complete Decimal to H:MM Reference Table
| Decimal Hours | H:MM Format | Total Minutes | Common Context |
|---|---|---|---|
| 0.10 | 0h 06m | 6 min | Law firm minimum billing unit (1 tenth) |
| 0.20 | 0h 12m | 12 min | 2 tenths (two minimum billing units) |
| 0.25 | 0h 15m | 15 min | Quarter-hour (consulting billing minimum) |
| 0.30 | 0h 18m | 18 min | 3 tenths billing unit |
| 0.40 | 0h 24m | 24 min | 4 tenths billing unit |
| 0.50 | 0h 30m | 30 min | Half hour (ADP, payroll standard) |
| 0.60 | 0h 36m | 36 min | 6 tenths billing unit |
| 0.70 | 0h 42m | 42 min | 7 tenths billing unit |
| 0.75 | 0h 45m | 45 min | Three-quarter hour |
| 0.80 | 0h 48m | 48 min | 8 tenths billing unit |
| 0.90 | 0h 54m | 54 min | 9 tenths billing unit |
| 1.00 | 1h 00m | 60 min | Full hour, exact |
| 1.25 | 1h 15m | 75 min | 1 hour 15 minutes |
| 1.50 | 1h 30m | 90 min | 1 hour 30 minutes |
| 1.75 | 1h 45m | 105 min | 1 hour 45 minutes |
| 2.00 | 2h 00m | 120 min | 2 hours exactly |
| 2.25 | 2h 15m | 135 min | 2 hours 15 minutes |
| 2.50 | 2h 30m | 150 min | 2 hours 30 minutes |
| 2.75 | 2h 45m | 165 min | 2 hours 45 minutes |
| 3.33 | 3h 20m | 200 min | Non-round decimal (repeating) |
Three Real US Billing Scenarios: Timesheet Decimal Conversion in Practice
Immigration Attorney in Houston Billing Five Client Matters at $375 Per Hour
An immigration attorney in Houston tracks time in handwritten notes throughout the day and enters the H:MM records into Clio (legal billing software) each evening. One Tuesday she works on: Client A visa application 47 minutes, Client B green card status call 8 minutes, Client C deportation defense research 2 hours 17 minutes, Client D employment authorization document 33 minutes, Client E naturalization interview prep 1 hour 4 minutes. Converting each to decimal and rounding UP to 0.1h: 47 min = 0.7833h, rounds to 0.8h. 8 min = 0.1333h, rounds to 0.2h (two billing units since any time over 0.1h = next tenth). 2h 17m = 2.2833h, rounds to 2.3h. 33 min = 0.55h, rounds to 0.6h. 1h 4m = 1.0667h, rounds to 1.1h. Total billed: 0.8 + 0.2 + 2.3 + 0.6 + 1.1 = 5.0h at $375/hr = $1,875.00. Total actual time worked: 47+8+137+33+64 = 289 minutes = 4.8167h. The 0.2h rounding premium over actual time (12 minutes) at $375/hr is $75.00, representing the billing premium inherent in the 0.1h rounding-up system.
IT Consultant in Austin Converting a Decimal Invoice Back to H:MM to Audit a Client Bill
An Austin tech startup received a consulting invoice from their IT vendor showing “Network security audit: 6.3 hours at $200/hr = $1,260.00.” The startup’s CFO wants to verify this is reasonable and converts 6.3 decimal hours back to H:MM format: 6.3h = 6 hours + (0.3 x 60 minutes) = 6 hours + 18 minutes = 6h 18m. The CFO checks her records showing the consultant was on-site from 9:15 AM to 3:40 PM, which is 6 hours 25 minutes. Converting 6h 25m: 6 + (25/60) = 6.4167h. At quarter-hour billing, 6h 25m rounds up to 6.5h, not 6.3h. At 0.1h billing, 6h 25m rounds up to 6.5h. The vendor billed 6.3h, which is 6h 18m, a full 7 minutes less than actual time on-site even without rounding. The CFO uses this reverse conversion to identify the discrepancy before paying.
CPA Firm in Chicago Comparing 0.1h vs 0.25h Billing on a Tax Return Engagement
A CPA at a mid-size Chicago accounting firm is deciding whether to bill in tenths of an hour (0.1h increments, 6 minutes each) or quarter-hours (0.25h increments, 15 minutes each) for a new client’s business tax return engagement. The work log shows: Initial client meeting 1h 7m, Document collection review 43m, Federal return preparation 3h 22m, State return preparation 1h 15m, Partner review 28m, Client delivery call 14m. Total actual: 406 minutes = 6.7667h. Under 0.1h rounding (each entry rounded up): 1.2 + 0.8 + 3.4 + 1.25 + 0.5 + 0.3 = 7.45h billed. Under 0.25h rounding (each entry rounded up): 1.25 + 0.75 + 3.5 + 1.25 + 0.5 + 0.25 = 7.50h billed. At $225/hr: tenths billing = $1,676.25, quarter-hour billing = $1,687.50. The difference is only $11.25 here, but across hundreds of engagements per year the billing method choice has meaningful revenue implications.
Four Expert Tips for Professional Timesheet and Billing Decimal Conversion
Always Round Each Individual Entry, Never the Total: The Law Firm Rule
The professional billing standard is to round each time entry individually, then sum the rounded entries. Do not sum the actual times first and then round the total. Example: three phone calls of 4 minutes, 4 minutes, and 4 minutes (total 12 minutes actual). Per-entry rounding: each 4-minute call rounds UP to 0.1h, so 3 x 0.1h = 0.3h billed. Total-then-round: 12 minutes total = 0.2h billed. The per-entry method bills 0.3h; the total-then-round method bills 0.2h. Law firms universally use per-entry rounding because each matter, task, or client is tracked separately in billing software. This calculator applies per-entry 0.1h rounding to each row independently before summing.
0.1h vs 0.25h: Which Billing Increment Is Standard in Your Profession
Law firms in the US almost universally use 0.1-hour (6-minute) billing increments. This is the standard taught in law school and embedded in every major legal billing platform including Clio, TimeSolv, PracticePanther, MyCase, and Bill4Time. Accounting and financial advisory firms typically use either 0.1h or 0.25h increments depending on firm culture. IT consultants, management consultants, and marketing agencies more commonly use 0.25h (15-minute) increments. The ABA’s Model Rules of Professional Conduct do not specify a billing increment, but billing ethics rules require that time billed bears a reasonable relationship to time actually worked. Both 0.1h and 0.25h methods are ethically accepted when rounding is neutral in its design, even if each individual round-up benefits the biller.
The Repeating Decimal Trap: Why 1/3 Hour Is Not Exactly 0.33
Twenty minutes is exactly one-third of an hour, so 20 minutes = 0.3333… repeating. If you enter 0.33 as a decimal and convert back to H:MM, you get 19 minutes and 48 seconds (0.33 x 60 = 19.8 minutes), not 20 minutes. The 12-second discrepancy compounds when you sum several entries. This calculator uses exact arithmetic: when you enter 0h 20m, it computes 0.3333h internally and displays 0.3333 rounded to 4 decimal places. The reverse conversion from 0.3333 gives back 20 minutes (0.3333 x 60 = 19.998, rounded to 20). Non-round decimals like 0.1667h (10 minutes), 0.3333h (20 minutes), and 0.6667h (40 minutes) all involve repeating decimals. Always convert to 4 decimal places and avoid the 2-decimal shortcut when precision is critical.
Billing Software Exports: Why Your Report Shows 2.30 but You Worked 2h 17m
Legal and accounting billing software like Clio, QuickBooks Time, and Harvest export time in decimal format. When you export a billing report and see “2.30 hours,” the software has already applied 0.1h rounding to your original 2h 17m entry (2h 17m = 2.2833h, rounded up to 2.3h). The exported decimal is the billed time, not the raw time. When auditing a billing export, always use the reverse conversion (Decimal to H:MM) to reconstruct what the original H:MM entry was before rounding, then compare to your time log. This is also how clients auditing their invoices verify whether time has been correctly rounded versus inflated.
Time Billing Software Used by US Professionals: How Each Handles Decimals
Legal Billing Software: Clio, TimeSolv, PracticePanther
Clio is the most widely used legal practice management software in the US, with over 150,000 law firm customers. Clio’s time tracking module allows entry in HH:MM format (“1:30” for 1 hour 30 minutes) or decimal (“1.5h”). Clio applies per-entry rounding based on the firm’s billing increment setting (most firms set it to 0.1h). When you export a Clio billing report to Excel or PDF, the time values appear in decimal format. Understanding that 1.5 = 1h 30m, 2.3 = 2h 18m, and 0.8 = 0h 48m is essential for reviewing Clio invoices. TimeSolv and PracticePanther work the same way; all three platforms bill to the nearest 0.1h increment by default.
Accounting and Productivity Platforms: QuickBooks Time, Harvest, Toggl
QuickBooks Time (formerly TSheets) is the most common time tracking tool for small businesses using QuickBooks payroll. It tracks time in HH:MM internally but exports decimals for payroll and billing reports. Harvest is popular among agencies, consultants, and freelancers and shows both formats in its reports. Toggl Track displays time in HH:MM in the app but exports decimal hours in CSV reports. When a Toggl report shows 8.25 hours, that is 8 hours 15 minutes. When Harvest shows 6.5 billable hours, that is 6 hours 30 minutes. All three tools assume the user knows how to interpret decimal hours; this calculator serves as the reference when the format is unclear.
Freelancer and Contractor Billing: Tracking Billable vs Non-Billable Time
Independent contractors face a unique challenge that salaried employees do not: the distinction between billable and non-billable time. Every hour a freelance designer spends pitching new business, updating their portfolio, attending industry events, or handling administrative tasks is real work but earns nothing directly. The time that does earn money must be tracked precisely and billed accurately. A freelance copywriter who bills 20 hours per week at $85/hr earns $88,400 per year before taxes, but only if every billable hour is captured and correctly converted to decimal for invoice generation.
Most freelancers use apps like Toggl, Clockify, or Harvest to track time. All three export decimal hours in their reports. A Toggl weekly summary showing “Design work: 12.83 hours” means the designer worked 12 hours 49 minutes and 48 seconds on billable design tasks. Converting 12.83h to H:MM: 12 hours + (0.83 x 60) = 12 hours + 49.8 minutes = 12h 50m. The 0.03h discrepancy (about 1.8 minutes) explains why checking the decimal-to-H:MM reverse conversion against your raw time log matters even with tracking software. Apps can aggregate multiple sessions in ways that introduce small rounding differences from the original entries.
For 1099 independent contractors, every dollar of billing revenue is gross self-employment income subject to both income tax and self-employment tax (15.3% on the first $168,600 in 2024). Accurate invoicing means accurate tax basis: overbilling costs client relationships, and underbilling directly reduces your net income. The IRS expects 1099 income to match client-issued 1099-NEC forms, which report what clients paid. If your invoices and client 1099s differ significantly, document the discrepancy or expect IRS scrutiny. Precise decimal conversion is the foundation of accurate professional invoicing.
The History of Tenths Billing: How 0.1h Became the US Law Firm Standard
The 0.1-hour (6-minute) minimum billing unit was not always the US legal standard. In the 1960s and earlier, attorneys often billed in quarter-hours (0.25h increments) or even in flat fees per matter. The shift to 0.1h billing accelerated in the 1970s and 1980s as large law firms grew and computerized billing systems made per-entry time recording practical. The ABA Commission on Billable Hours in 2001 studied time-tracking practices and found tenths-of-an-hour billing firmly entrenched at most US law firms, particularly at large corporate firms. The system has been criticized for incentivizing more total billable hours over efficiency, but it remains the dominant billing standard in US legal practice in 2025.
Alternative fee arrangements (AFAs) including flat fees, contingency fees, blended hourly rates, and success fees have gained traction since the 2008-2009 financial crisis, when corporate clients began pushing back on hourly billing growth. But even in AFAs, the underlying time tracking still uses the same decimal conversion system to inform fee estimates, evaluate attorney productivity, and set future flat fee amounts based on historical time data. Understanding the decimal conversion system is essential whether you bill hourly or use AFAs.
State bar fee dispute arbitration programs are another reason time tracking accuracy matters. If a client disputes a legal bill, the attorney must be able to produce contemporaneous time records showing what work was done, when, and for how long. Billing software exports showing 2.3h for “Research re: contract interpretation” must be backed by a time entry showing the start and end of that research session. The reverse conversion from 2.3h to 2h 18m is the bridge between the invoice and the underlying time record. Attorneys who cannot reconcile their billed decimals to actual work times are at a disadvantage in fee disputes.
Billing Ethics and Write-Downs: When Billed Hours Differ from Worked Hours
Professional billing involves two categories that this calculator does not handle but that every professional should understand: write-ups and write-downs. A write-up means billing more than the time actually worked, for example billing 3.0h for work that only took 2.5h because the matter was unusually complex or required specialized expertise. Write-ups are rare and ethically questionable in law; the ABA Model Rules require that fees be reasonable, and inflating time beyond actual work may violate Rule 1.5. A write-down means billing less than the time actually worked, which is common and ethically unproblematic. An attorney who took 5.0h on a simple task due to inexperience may write the bill down to 3.0h because that is what a client would reasonably expect to pay for the work.
Corporate legal departments and sophisticated clients often audit outside counsel bills using e-billing software (eBillingHub, TyMetrix, BrightFlag) that flags unusual time entries, reviews billing narratives for vague descriptions, and compares hours per task against benchmarks. These systems convert all billed time to decimals for statistical analysis. An outside firm’s 0.5h entry for “review email” may be flagged if the client’s billing guidelines specify a 0.1h maximum for reviewing a single email. Understanding the decimal values behind billing entries is fundamental to managing legal costs as both a client and a service provider. This calculator can be used by both sides in a billing audit.
Converting Non-Round Decimals: The 1/3 and 2/3 Hour Problem
Some of the most frequently encountered billing decimals involve fractions that do not terminate: 0.1667h (10 minutes = 1/6 hour), 0.3333h (20 minutes = 1/3 hour), 0.6667h (40 minutes = 2/3 hour). Billing software that stores time as H:MM internally avoids this issue by working in whole minutes. But if you import a decimal from one system into another and it gets truncated at 2 decimal places, 0.33h instead of 0.3333h introduces a 1.2-minute error per entry. Over 20 such entries per day across 250 billable days, that is 100 hours per year of cumulative billing discrepancy from a 2-decimal truncation choice in the billing system configuration. This is why enterprise billing systems store and export to 4 decimal places, and why this calculator displays 4-decimal results even when 2-decimal precision looks sufficient for a single entry viewed in isolation.
Quick Reference: H:MM to Decimal Conversion for Common Billing Entry Times
| Time Worked | Exact Decimal | Bill at 0.1h | Bill at 0.25h | Revenue Diff. at $300/hr |
|---|---|---|---|---|
| 5 minutes | 0.0833h | 0.1h | 0.25h | $45.00 ($30 vs $75) |
| 10 minutes | 0.1667h | 0.2h | 0.25h | $15.00 ($60 vs $75) |
| 15 minutes | 0.2500h | 0.3h | 0.25h | $15.00 ($90 vs $75) |
| 20 minutes | 0.3333h | 0.4h | 0.25h | $45.00 ($120 vs $75) |
| 30 minutes | 0.5000h | 0.5h | 0.5h | $0 (tie) |
| 45 minutes | 0.7500h | 0.8h | 0.75h | $15.00 ($240 vs $225) |
| 1h 00m | 1.0000h | 1.0h | 1.0h | $0 (tie) |
| 1h 07m | 1.1167h | 1.2h | 1.25h | $15.00 ($360 vs $375) |
| 2h 17m | 2.2833h | 2.3h | 2.5h | $60.00 ($690 vs $750) |
| 3h 22m | 3.3667h | 3.4h | 3.5h | $30.00 ($1,020 vs $1,050) |
Frequently Asked Questions About Timesheet Decimal Conversion
0.1 hours equals exactly 6 minutes. This is the standard minimum billing unit used by US law firms. The calculation: 0.1 x 60 = 6 minutes. A quick reference for all tenths: 0.1h=6min, 0.2h=12min, 0.3h=18min, 0.4h=24min, 0.5h=30min, 0.6h=36min, 0.7h=42min, 0.8h=48min, 0.9h=54min, 1.0h=60min. Law firms bill all time in 0.1-hour increments because any task, even a 1-minute phone call to leave a voicemail, is billed as a minimum 0.1h (6 minutes). This is ethically accepted under ABA billing guidelines, provided the attorney does not double-bill for the same 6-minute block across multiple clients.
0.25 hours equals exactly 15 minutes. This is one quarter of an hour, which is why it is called a “quarter-hour.” Quarter-hour billing (0.25h increments) is the standard for IT consultants, management consultants, and many accounting firms. Common quarter-hour values: 0.25h=15min, 0.50h=30min, 0.75h=45min, 1.00h=60min, 1.25h=75min, 1.50h=90min. Under quarter-hour billing, a 10-minute call rounds up to 0.25h (15 minutes). Under tenths billing, a 10-minute call rounds up to 0.2h (12 minutes). Quarter-hour billing therefore produces higher invoices for short tasks but produces the same or lower invoices as tenths billing for longer tasks that happen to end close to a quarter-hour mark.
0.5 hours equals exactly 30 minutes. This is one of the cleanest conversions: 0.5 x 60 = 30. Half-hour blocks (0.5h) appear in payroll timesheets, billing records, and scheduling software. In payroll: a 30-minute break might or might not be compensable (generally compensable under FLSA if under 20 minutes, not compensable if a meal break where the employee is fully relieved). In billing: 30 minutes is a natural meeting length and appears as 0.5h on every billing statement. 0.5h is also equidistant between the 0.1h billing round-up and the 0.25h billing round-up, so both methods produce the same result for exactly 30 minutes.
0.75 hours equals exactly 45 minutes. The calculation: 0.75 x 60 = 45. Three-quarters of an hour (0.75h) appears frequently in payroll timesheets (a shift ending 45 minutes before the hour), billing records (a 45-minute client meeting billed as 0.75h), and project management tools. In payroll: 7h 45m = 7.75 decimal hours. In billing: 45 minutes exactly fills one 0.75h block under quarter-hour billing. Under tenths billing, 45 minutes = 0.75h, which is exactly 7.5 tenths, so it rounds up to 0.8h. This is one of the cases where 0.1h rounding actually produces a higher bill (0.8h) than 0.25h rounding (0.75h) for the same time worked.
Lawyers track each task separately and round each task’s time UP to the nearest 0.1 hour (6 minutes) before recording it in billing software. The process: note start and end time for each task, compute elapsed time in minutes, divide by 60 for the exact decimal, round up to the nearest 0.1h. A task taking 7 minutes rounds up to 0.2h (12 minutes billed). A task taking exactly 12 minutes is 0.2h exactly (no rounding needed). A task taking 13 minutes rounds up to 0.3h (18 minutes billed). Law firms train new associates to never record less than 0.1h for any task that involves active work. The ABA recommends recording all time contemporaneously rather than reconstructing it at the end of the day, because reconstruction invariably underestimates actual time.
6 minutes equals exactly 0.1 decimal hours (6/60 = 0.1). This is the standard minimum billing unit for US law firms. Any task that takes between 1 and 6 minutes is billed as 0.1h under the standard rounding-up system. 12 minutes = 0.2h. 18 minutes = 0.3h. Every 6 additional minutes adds 0.1h to the bill. At $350/hr (a mid-range attorney rate), each 0.1h increment is worth $35. A 30-second phone call to confirm an appointment is still billed as 0.1h = $35 under standard law firm billing ethics. Many corporate clients negotiate billing guidelines that require a description for any entry under 0.2h, or that cap minimum billing at 0.1h for short administrative tasks.
1.5 hours = 1 hour and 30 minutes. The calculation: the whole number (1) is hours. The decimal (0.5) times 60 = 30 minutes. So 1.5h = 1h 30m. This is one of the most common conversions: 1.5 hours is a standard meeting length, a half-day billing block, or a common time increment in consulting estimates. Other common 1-to-2 hour conversions: 1.25h = 1h 15m. 1.33h = 1h 20m. 1.5h = 1h 30m. 1.67h = 1h 40m. 1.75h = 1h 45m. 1.83h = 1h 50m.
2.75 hours = 2 hours and 45 minutes. The calculation: whole number = 2 hours. Decimal: 0.75 x 60 = 45 minutes. So 2.75h = 2h 45m = 165 total minutes. 2.75h is commonly billed for a workshop, extended client presentation, or a complex contract review. At $300/hr: 2.75 x $300 = $825.00. At $250/hr: 2.75 x $250 = $687.50. The reverse calculation entering 2.75 in the Decimal to H:MM tab of this calculator gives back 2h 45m instantly.
One hour equals 10 tenths of an hour. Each tenth (0.1h) is 6 minutes, and 10 x 6 = 60 minutes = 1 hour. This is why law firm billing works intuitively once you memorize the 6-minute increment: simply count how many 6-minute blocks are in your work time. 12 minutes = 2 tenths. 30 minutes = 5 tenths. 60 minutes = 10 tenths = 1.0h. A full workday of 8 hours contains 80 tenths. An attorney who bills 6.5 hours in a day has billed 65 tenths. Each tenth is a minimum discrete unit of work. Most legal billing software and billing software export reports show hours in decimal format (e.g., 6.5h not 6:30).
0.3 hours equals exactly 18 minutes. The calculation: 0.3 x 60 = 18. Three tenths of an hour appears frequently in law firm billing for short but substantive tasks: reviewing and signing a one-page document, returning a phone call with a brief update, or sending an email with legal advice. On an invoice: “Review client email re: contract terms: 0.3h @ $400/hr = $120.00.” In payroll: a shift of 8h 18m = 8.3h decimal. 0.3h is one of the exact tenths that does not involve a repeating decimal, so the conversion from minutes to decimal (18/60 = 0.3 exactly) and back is clean.
45 minutes = 0.75 decimal hours. The calculation: 45/60 = 0.75 exactly. Forty-five minutes is three-quarters of an hour and one of the cleanest conversions alongside 15 min (0.25), 30 min (0.5), and 60 min (1.0). In payroll: a shift of 7h 45m = 7.75h. In billing: a 45-minute client call billed at 0.1h rounding rounds up to 0.8h (since 45 min = 0.75h, which is not on a 0.1h boundary, so it rounds to 0.8h). Under 0.25h rounding, 45 minutes is exactly 0.75h and needs no rounding. This is one of the few cases where exact-quarter-hour work produces different results under the two billing methods: 0.1h billing = 0.8h, 0.25h billing = 0.75h.
A 0.1 billable hour entry on a law firm invoice means the attorney spent time on a task and is billing for a minimum of 6 minutes (0.1 x 60 = 6 minutes). The actual time spent may have been anywhere from 1 second to 6 minutes; any time up to 6 minutes rounds up to 0.1h under standard law firm billing. Common examples of 0.1h entries: sending a brief email, reviewing a one-page letter, leaving a voicemail, verifying an address, or docketing a court date. At $400/hr, a 0.1h entry costs the client $40 regardless of whether the task took 30 seconds or 6 minutes. This is ethically acceptable under ABA Model Rules, but clients negotiating engagement letters sometimes cap minimum billing at 0.1h per task-type category.
1.25 hours = 1 hour and 15 minutes. Calculation: whole number = 1 hour. Decimal: 0.25 x 60 = 15 minutes. Total minutes: 1.25 x 60 = 75 minutes. This conversion is clean and exact because 0.25 is exactly one-quarter. 1.25h is a common billing block for strategy calls, initial consultations, and brief document drafting sessions. On a timesheet: entering “1h 15m” in this calculator’s H:MM to Decimal mode gives 1.2500h (4 decimal places). On an invoice at $300/hr: 1.25 x $300 = $375.00 exactly.
90 minutes = 1.5 decimal hours. The calculation: 90/60 = 1.5 exactly. Ninety minutes (1.5h) is the standard duration for a full jury deliberation session, a typical mediation opening statement, and many client intake interviews. In payroll: a 9h 30m shift = 9.5h decimal. In billing: 90 minutes = 1.5h; under 0.1h rounding it stays 1.5h (already on a billing boundary); under 0.25h rounding it also stays 1.5h. At $350/hr: 1.5 x $350 = $525.00. 90 minutes is also exactly 5400 seconds, 1/8 of a standard 12-hour day, and 3.75% of a 40-hour workweek.
A timesheet is the raw record of hours worked, typically in H:MM format (7:30, 8:20). Payroll hours are what the payroll system processes, always in decimal format (7.50, 8.33). Billing hours are a third category: the billable time invoiced to clients, which may differ from both raw timesheet time (due to billing caps, write-downs, or write-ups) and payroll hours (because billing includes only client-billable work, not administrative time, training, or overhead). An attorney might work 9 hours on a given day (payroll hours: 9.00h) but bill only 7.5 hours to clients (billing hours: 7.5h), with the remaining 1.5 hours spent on firm administration that is not billable. This calculator handles both payroll-style total conversion and billing-style per-entry rounding.
2.5 hours = 2 hours and 30 minutes. Calculation: whole number = 2 hours. Decimal: 0.5 x 60 = 30 minutes. Total minutes: 2.5 x 60 = 150 minutes. This is a clean exact conversion because 0.5 is exactly one-half. 2.5h appears in billing for depositions, arbitration sessions, and extended document review blocks. In payroll timesheets: a shift of 2h 30m = 2.5h decimal for entry into ADP or QuickBooks. At $200/hr: 2.5 x $200 = $500.00 exactly. 2.5h is also commonly used in project management as a standard task duration estimate (“2.5 hours for initial setup”).
Related Payroll and Time Calculators
Legal Disclaimer and Editorial Transparency
This timesheet decimal converter is provided for general informational and professional time-tracking purposes only. It does not constitute legal, accounting, tax, or HR compliance advice. Billing practices discussed reflect common US professional standards as of the content publication date; individual law firms, accounting firms, and consulting practices may set their own billing increment policies that differ from the 0.1h and 0.25h methods described here. ABA Model Rules of Professional Conduct cited are general references; state bar ethics rules and specific engagement letter terms govern actual billing obligations. Clients who believe billing entries are inaccurate should raise concerns directly with the billing attorney or accountant and may consult their state bar’s fee dispute resolution program. This calculator uses standard arithmetic (floating-point with Big.js for monetary amounts) and standard rounding rules. Verify all billing calculations against your original time records. Key professional references: American Bar Association at americanbar.org; DOL wage and hour guidance at dol.gov/agencies/whd; IRS self-employment guidance at irs.gov.