The full quarter-hour conversion chart
Below is the complete decimal time conversion chart in 15-minute steps from 0:15 all the way to 12:00, showing clock time, decimal hours and total minutes side by side. It covers every value a quarter-hour rounding payroll system can produce, including the everyday anchors like 7:30 (7.5), 8:15 (8.25) and 8:45 (8.75). Find the row, read across, done.
The chart reads in both directions. Coming from a timesheet, look up the clock time and take the decimal; coming from a paycheck or report, find the decimal and read the clock time back. Because the three columns agree by construction, it is also a quick way to teach the pattern: each 15 minutes is exactly .25 of an hour.
The structure is deliberately regular so the eye can jump without scanning every row. Whole hours sit on the .00 values, quarters fill in between, and every 0:15 step adds 0.25 to the decimal column and 15 to the minutes column. Once you see that three-way rhythm — quarter hour, quarter decimal, 15 minutes — you can predict any row from its neighbor without actually reading it.
The payroll values everyone memorizes
Four conversions carry most of the day-to-day weight, and they are worth committing to memory outright: 7.75 is 7 hours 45 minutes, 8.25 is 8 hours 15 minutes, 4.25 is 4 hours 15 minutes, and 6.75 is 6 hours 45 minutes. Notice the rule hiding inside them — the digits after the decimal point are the minutes in quarter-hours, so .25 means 15 minutes, .50 means 30, and .75 means 45. Every value on the chart follows from that one sentence.
These four show up constantly because they are the natural outputs of ordinary shifts. A 7:45 day is a standard 8-hour shift with a quarter hour trimmed; an 8:15 day is a shift that ran a little long; a 4:25 entry usually means 4 hours 15 minutes plus a rounding step somewhere upstream. When a figure like 7.75 appears on a pay stub, being able to read it instantly as seven forty-five is the difference between trusting the stub and staring at it.
A quick self-test before you close the page: what is 5.5 in hours and minutes? If you answered 5 hours 30 minutes without looking, you have internalized the chart's logic. If you hesitated, bookmark the page — even a few days of glancing at the rows embeds the quarter-hour pattern for good.
Why 15-minute steps cover most payroll
The majority of time-and-attendance systems round punches to the nearest quarter hour, so paid time almost always lands on a value in this chart. That includes the big payroll providers and most scheduling apps — their reported decimals are simply rows of this table. When a figure is not on the chart, it means the underlying system tracked exact minutes, and the converters on this site handle those values to four decimal places.
For staff who total handwritten timecards, the chart doubles as an adding aid: convert each day's minutes using the rows, add the decimals, and the weekly total is ready to enter. Auditors use it the opposite way — decode a payroll decimal into minutes and compare it with the original punches.
There is a second reason the quarter hour dominates: it is the largest rounding increment that stays comfortably fair to both sides. The FLSA accepts neutral rounding to 5, 6 or 15 minutes, but 15-minute rounding moves a punch by up to 7.5 minutes — enough that employers must apply it evenhandedly to stay compliant. If a stub's decimals never leave the .00/.25/.50/.75 grid, you are looking at quarter-hour rounding, and this chart is that system's complete vocabulary.
The tenth-hour table: 0.1 through 0.9 of an hour
Not every workplace rounds to the quarter. Many legal, consulting and professional-services timekeepers bill in tenths of an hour, and that system has its own mini-chart: 0.1 is 6 minutes, 0.2 is 12 minutes, 0.3 is 18 minutes, 0.4 is 24 minutes, 0.5 is 30 minutes, 0.6 is 36 minutes, 0.7 is 42 minutes, 0.8 is 48 minutes, and 0.9 is 54 minutes. The step is a constant 6 minutes, which is why tenth-hour systems are sometimes called 6-minute billing.
Reading a tenth-hour figure is a two-step multiply: the whole number is hours, and the tenth digit times 6 is the minutes. A 2.7 hour entry is 2 hours and 7 × 6 = 42 minutes. In reverse, a 33-minute phone call is 33 ÷ 6 = 5.5 tenths, which rounds up to 0.6 on most billing systems — one of the reasons legal invoices creep upward at the margins.
The tenth table and the quarter chart coexist on this page on purpose. Some teams run a hybrid: attendance and payroll round to the quarter hour, while billable work logs in tenths. Keeping both ladders in view lets you translate between the two — 0.25 and 0.4 are the same 24-minute neighborhood, but one is a payroll decimal and the other an invoice decimal, and mixing them up is a classic bookkeeping mistake.
Quarter-hour rounding and the 7-minute rule
Under quarter-hour rounding as recognized in 29 CFR 785.48(b), clock punches are snapped to the nearest 15 minutes, and the practical shorthand is the 7-minute rule: punches within 7 minutes of a quarter line round down, and 8 or more minutes round up. A punch at 8:07 rounds to 8:00; a punch at 8:08 rounds to 8:15. In decimal terms the chart's .25-per-step grid is exactly where every rounded punch can land.
The regulation's key requirement is neutrality: rounding must average out for the employee over time, not systematically favor the employer. Rounding only the in-punch down and the out-punch up would fail that test, and so would a system configured to always round in the company's favor. When applied evenhandedly, early and late punches cancel out, and the chart's rows describe the week accurately in aggregate.
For workers, the 7-minute rule explains those small stub discrepancies that feel arbitrary. Arrive at 7:53, leave at 16:52, and a quarter-hour system may pay 8:00 to 16:45 — a 7-minute shortfall from the true elapsed time. On its own that is noise; if the same direction repeats every day, it is a pattern worth raising, because neutrality is a legal requirement, not a courtesy.
Handwritten timesheets and printed wall charts
The most loyal users of a chart like this are the ones filling in paper. Handwritten timesheets — a clipboard at a job site, a spiral notebook at a salon, the laminated card taped by a shop clock — still record hours-and-minutes, while the payroll portal on the other end wants decimals. The chart is the bridge: read each day's entry off the paper, find the row, write the decimal into the portal.
Printing the chart and taping it where timesheets get filled is the single highest-leverage move. It eliminates the mental division of minutes by 60 at the exact moment the totals are being written, which is when transcription errors are born. A wrong entry of 8.5 for 8:30 is harmless; the dangerous ones are values like 8:45 becoming 8.45 — a decimal that looks right, is wrong by more than a quarter hour, and multiplies across a whole crew if the habit spreads.
Shops that switch their handwritten cards to decimal entry at the source report fewer corrections later. Instead of writing 7:30 and letting someone convert it, the writer checks the chart once and records 7.5 immediately. From then on, adding the week's numbers is plain decimal arithmetic, and the weekly total arrives at payroll already in the format the system expects.
Building the chart in Excel with VLOOKUP
If your team lives in spreadsheets, this chart translates directly into an Excel lookup table. Put the clock times in one column (0:15, 0:30, 0:45 … 12:00) and the decimal hours in the next (0.25, 0.5, 0.75 … 12). Then a formula like VLOOKUP(A2, ChartRange, 2, TRUE) — with range_lookup set to TRUE for approximate match — takes any raw time in A2 and snaps it to the nearest row at or below it, returning the matching decimal. That is precisely how a rounding table works in practice.
The approximate-match trick deserves a caveat. TRUE matching finds the largest chart value that does not exceed the lookup value, so an entry of 8:14 returns 8.0, not 8.25. If you want true nearest-neighbor rounding instead of floor rounding, either add midpoints to the table (7:52.5 boundaries, or simply 8:07.5 mapping up) or wrap the logic differently. Test the boundary cases — 8:07 and 8:08 — before trusting the column.
Excel can also skip the table entirely: multiply a proper time value by 24 (formatted as a number, not a time) to get decimal hours, so 8:30 × 24 = 8.5. The chart and the VLOOKUP approach earn their keep when the underlying data is messy text or when you need to enforce rounding policy visibly — a formula hides its assumptions, while a chart on the wall shows them to everyone.
How payroll software applies rounding options
Major payroll platforms each expose their own rounding controls, and all of them produce rows of this chart. ADP's time and attendance products let administrators choose increment rounding per punch pair — typically none, 5, 6, 15 or 30 minutes — applied at the in-punch, the out-punch, or the daily total. QuickBooks Time (formerly TSheets) offers quarter-hour and tenth-of-an-hour rounding on timesheet export, and Paychex supports similar neutral-rounding presets configured when the pay rules are set up.
The settings that matter are where the rounding is applied and whether it is symmetric. Rounding only at the daily-total level preserves individual punch times; rounding each punch rebuilds the day entirely out of chart rows. A crew whose stubs show exclusively .00/.25/.50/.75 decimals is being punch-rounded; a crew seeing 8.37 and 7.92 on the same stub is either unrounded or rounded only at the total. Knowing which mode your employer runs tells you exactly how to reconcile your own notes against the stub.
Administrators choosing a setting should reach for neutrality and simplicity together: 15-minute rounding is the easiest to explain to employees and the easiest to audit against this chart, while 6-minute (tenth-hour) rounding gives finer granularity for industries that bill by the tenth. Either is defensible under the FLSA when applied evenhandedly; an undocumented or one-sided setting is where audits start.
15-minute vs 6-minute increments across industries
The increment a field chooses is rarely arbitrary — it tracks how the work is billed. Law firms, accountants and consultants overwhelmingly use 6-minute (tenth-hour) increments because time is invoiced to clients: a 0.1 minimum unit is the industry convention for recording a short call or a quick review. Construction, manufacturing, healthcare and retail use 15-minute increments because time is paid, not billed, and quarter-hour granularity matches both punch clocks and scheduling blocks.
The two systems meet in hybrid roles. A hospital pharmacist is paid on quarter hours but may log interventions in tenths; a field engineer bills a client in 0.1 units while the employer's payroll rounds to 0.25. In both cases the chart's two ladders — 6-minute steps and 15-minute steps — cover the translation, and the same elapsed time can legitimately produce two different decimals depending on which ladder it is read against.
The increment also sets the stakes of small errors. In a 6-minute system, one rounded unit is 0.1 hours — meaningful on an invoice with dozens of entries. In a 15-minute system, one misrounded punch is up to 0.25 hours, which is larger per event but occurs on fewer events. That is why legal billing disputes revolve around many small entries, while hourly payroll disputes usually turn on one or two punches.
Decimal durations and the ISO 8601 PT notation
A third duration notation appears in APIs, calendars and project tools: ISO 8601 durations, written PT followed by hours and minutes — PT8H15M is 8 hours 15 minutes, PT7H30M is 7.5 hours, PT45M alone is 0.75 hours. The letter P marks a duration, the T separates the time part from an optional date part, and the H and M markers remove every ambiguity that plain 8:15 style entry suffers.
The chart maps onto ISO durations one row at a time. Where the chart says 8.25 decimal hours, the ISO string is PT8H15M; where it says 2.5, the string is PT2H30M. Many APIs accept decimal hours as an alternative (8.25) but emit canonical durations in PT form, so anyone reading raw calendar exports or timesheet API responses ends up converting between all three: clock time, decimal, and PT notation.
A practical conversion habit: expand the PT string to hours-and-minutes first, then use the chart to reach the decimal — PT6H45M becomes 6:45, which the chart reads as 6.75. Going the other way, strip the decimal's whole hours as H and multiply the fractional part by 60 for M: 3.5 becomes PT3H30M. Neither direction requires arithmetic harder than a quarter-hour multiply, which is exactly what the chart already tabulates.
Using the chart for totals and overtime checks
Beyond single-day lookups, the chart is a fast instrument for weekly totals. Add the day rows in decimal — 7.75 + 8.0 + 8.25 + 7.5 + 6.75 = 38.25 — and the sum itself is a chart value: 38 hours 15 minutes. Decimal addition is where this format shines, because unlike clock arithmetic there is no carry at sixty; the hours column and the decimal column add independently, and mistakes are rare and visible.
Overtime checks become one comparison. A weekly total of 41.25 means 40 straight hours plus 1.25 overtime hours — one hour 15 minutes — and the premium math proceeds from there. Because the total stays on the quarter-hour grid when every daily entry does, the overtime figure inherits the same rounded basis the payroll system uses, which keeps your estimate and the stub in the same units instead of mixing exact and rounded time.
One caution when adding rounded entries: rounding error accumulates. Five days each rounded by up to 7.5 minutes can drift the weekly total by up to about 37 minutes versus exact time, which is why neutral rounding must be tracked at the policy level rather than repaired by hand. If your reconstructed total and the stub disagree by less than half an increment, the difference is almost certainly rounding, not an error worth disputing.
The arithmetic in each row: minutes divided by 60
Every row in the chart reduces to the same operation: take the minutes, divide by 60, and add the result to the whole hours. One minute is 1/60 of an hour, so 15 minutes is 15 ÷ 60 = 0.25, 30 minutes is 0.50, and 45 minutes is 0.75. Those three fractions are the skeleton of the entire table, and every other row hangs off them at 0.25-step intervals. Once you see that each quarter-hour step adds exactly 0.25, you can predict any row from its neighbor without looking.
Between the quarter-hour marks, each individual minute adds 0.0167 to the decimal — that is 1 ÷ 60, carried to four places. So 8:17 is 8 + 17/60 = 8.2833, and 8:23 is 8 + 23/60 = 8.3833. The gap between them is exactly 6 × 0.0167 = 0.1, which is why six minutes equals one tenth of an hour — a fact that drives legal billing and the <a href='/minutes-to-decimal-hours'>minutes to decimal hours</a> chart simultaneously.
The reverse direction runs the same multiplier in the other direction: take the decimal fraction and multiply by 60 to recover the minutes. A stub showing 38.42 hours decodes as 0.42 × 60 = 25.2 minutes, so 38:25. That round-trip check works on any value and catches two categories of error at once: a decimal that was built by writing minutes after the point instead of dividing them (7.45 for 7:45), and a stub figure whose minutes never correspond to a real clock time (7.73 is 7 hours 43.8 minutes, and payroll systems do produce those when they round at a daily total rather than per punch).
Three shift calculations: from clock time to decimal to dollars
A retail associate clocks in at 9:15 AM and out at 5:30 PM with a paid 15-minute break and no unpaid meal. Elapsed time is 8 hours 15 minutes. Because the break is under 20 minutes it is compensable under 29 CFR § 785.16, so nothing comes off — 8:15 goes on the card as-is. Chart lookup: 8:15 is 8.25 decimal hours. At $16.50 an hour, 8.25 × $16.50 = $136.13. If the associate had misread the chart row and entered 8.15 instead of 8.25, the day would calculate as $134.48 — a $1.65 error per shift that compounds to $429 over a full year of five-day weeks.
An office worker punches in at 8:45 AM and out at 17:20 PM, with a 45-minute unpaid lunch. Elapsed time is 8 hours 35 minutes; subtract the meal to get 7 hours 50 minutes paid. Chart lookup: 7:50 sits between 7:45 (7.75) and 8:00 (8.0), so the <a href='/'>decimal hours calculator</a> gives 7.8333 for the exact value. At $28 an hour, 7.8333 × $28 = $219.33. A common mistake here is subtracting the 45-minute lunch as 0.45 decimal hours rather than 0.75 — the latter is correct because 45 minutes is 45/60 = 0.75. Subtracting 0.45 leaves 8.15 instead of 7.8333 and overstates the day's pay by $8.87.
A hospital aide works 07:00 to 19:30 with a 30-minute unpaid meal. Elapsed time is 12:30; subtract 0:30 to get 12:00 paid — a clean chart row at 12.0 decimal hours. At $19 an hour in most states: 12.0 × $19 = $228. In California, Labor Code § 510 requires 1.5× the regular rate for hours 8 through 12 in a single day, so the math splits: 8 straight hours at $19 = $152, plus 4 overtime hours at $28.50 = $114, totaling $266. That $38 gap — $228 versus $266 — exists on the same 12-hour shift depending only on the state line. The decimal is identical; the multiplication rule changes.
Errors this chart stops before they reach payroll
The most costly single error in handwritten timesheets is writing the minutes after the decimal point instead of dividing them — entering 8.45 for 8:45 instead of 8.75. The gap is 0.30 hours, worth $6.60 at $22 an hour. Across five shifts a week and 50 working weeks, that habit costs $1,650 per year, and no payroll software catches it because 8.45 is a perfectly valid decimal. The chart eliminates the error by showing 8:45 → 8.75 on a single row lookup, with the division already done.
A related mistake is reading a decimal figure from left to right as if the digits after the point were minutes: interpreting 7.60 as "7 hours 60 minutes" rather than 7 hours 36 minutes (0.60 × 60 = 36). That reading overstates the day by 24 minutes. At $22 an hour, 24 minutes is $8.80 per occurrence. Anyone checking a timesheet by reading stubs against their own log will catch it instantly with the chart's right-to-left read: decimal column → clock-time column.
The third class of error appears during week totals on paper: carrying minutes past 59 in clock-notation addition. Adding 7:45 + 8:30 by hand gives "15 hours 75 minutes," which has to be manually converted to 16:15, and the conversion step is exactly where transcription mistakes breed. In decimal, 7.75 + 8.50 = 16.25, full stop — decimal addition has no carry at 60, no modular arithmetic, no correction step. The chart turns each day's clock entry into a decimal before the pen leaves the page, and the weekly sum becomes ordinary arithmetic. For the full week, the <a href='/time-card-calculator'>time card calculator</a> handles seven entries at once.
Precision on the job: quarter-hour steps versus six-minute steps
Quarter-hour rounding is the coarser of the two legal standards, and its cost is visible in dollars. Each 0.25 step at $22 an hour is $5.50. Under the 7-minute rule, a single punch can be moved up to 7.5 minutes — worth $2.75 at that rate. Five punches per day, five days a week: the maximum daily rounding drift is ±$13.75, and the FLSA requires that this drift averages to zero over time rather than always landing in the employer's favor. When a stub shows only .00, .25, .50 and .75 fractions, the employer is using quarter-hour rounding, and the chart's rows are the complete vocabulary of what they can charge or pay.
The six-minute increment — one tenth of an hour — is finer and carries higher per-entry stakes in billing. At $350 an hour, one tenth is $35. Law firms and consultants use this grid because client invoices demand visible precision: "0.3 hours — reviewed amended clause" is checkable in a way that "19 minutes" is not, and six minutes is the increment the billing system snaps every entry to. The tenth-hour table embedded in this page maps every 0.1 step from 0.1 to 0.9 with the matching minute count, so the two ladders — quarter-hour for payroll, sixth-of-an-hour for billing — live side by side for teams that run both.
Two-decimal display versus four-decimal precision is the third choice worth understanding. The chart shows two decimal places because payroll systems print two. But 8:23 is 8.3833, not 8.38 — the truncated version is 0.0033 hours short, about 12 seconds. One entry, fine. Add six such entries to build a weekly total and the display truncation can accumulate to several minutes of drift from the true sum. The safe practice: keep four decimal places in any spreadsheet column that will be summed, and let the two-decimal display happen only on the printed stub. The <a href='/decimal-to-time'>decimal to time converter</a> shows both two-place and four-place values to make that precision choice visible.
Common scenarios where the chart earns its place
A construction foreman fills in paper timecards for a six-person crew every Friday afternoon. Each card shows three or four clock-time entries per day — start, end, lunch, sometimes a split shift. Without the chart, converting each entry to decimal requires dividing by 60 six or seven times per card, thirty or forty times for the crew, under time pressure and with the week's mud still on the hands. With the chart taped to the clipboard, each clock time gets one glance and one number written — no arithmetic at all. Errors drop because the lookup step is slower than the mental-math step, giving the foreman time to notice a 7:45 that should have been 8:15.
A small law firm's billing assistant reconciles attorney time entries every Tuesday morning. The entries arrive as clock durations — 1:20, 0:45, 2:10 — but the billing platform expects decimal hours in 0.1-hour increments. The tenth-hour column in this chart converts each entry directly: 1:20 → 1.33 exact, billed as 1.4 after rounding up; 0:45 → 0.75, billed as 0.8; 2:10 → 2.17, billed as 2.2. All three lookups take under a minute. The same chart, same morning, handles the payroll side — the assistant is paid by the hour on a quarter-hour grid, so her own timesheet reads off the same table's other column.
A payroll clerk at a regional hospital audits the prior week's nurse timesheets before approving the batch. Most shifts run close to 12 hours, and the decimal column on approved timesheets reads 11.75, 11.5, 11.25, 12.0. Any entry outside those quarter-hour values means either exact-minute tracking or a rounding exception — both of which require a second look. The clerk uses this chart as a filter: rows that match the quarter-hour grid pass quickly; anything between rows goes to the <a href='/hours-to-decimal'>hours to decimal</a> calculator for a precise check against the punch record. The chart's regularity is the signal; anomalies stand out precisely because they break the pattern.
Using this chart on mobile, on paper, and across tools
On a phone, the chart renders as a scrollable table with tap-target rows large enough to use one-handed. Pinch-to-zoom is not required. Screen readers announce each cell in the pattern "8 hours 30 minutes, 8 point 5 decimal hours, 510 minutes" — the three-column structure is marked up as a proper HTML table, so navigation by row and column works the same way any accessible data table does. Adding the page to a phone's home screen takes two taps in Safari or Chrome and opens the chart in a dedicated shortcut with no browser chrome in the way.
For teams filling paper timecards at a shop clock, job-site clipboard or salon front desk, a printed copy taped near where the cards get written is the single most effective accuracy upgrade available. It eliminates the mental division at the exact moment entries are being made — which is when transcription errors happen. A card that records 7.75 at the source never needs to be converted later; the decimal travels through the week without any further handling. Shops that switch to decimal-at-source report fewer payroll corrections because the error opportunity disappears rather than being caught after the fact.
For values between chart rows, for entries over 12 hours, or for totaling a full week, the companion tools cover the gaps. The <a href='/'>decimal hours calculator</a> converts any hours-and-minutes entry in both directions with four decimal places of precision. The <a href='/minutes-to-decimal-hours'>minutes to decimal hours</a> page lists every single minute from 1 to 60 for jobs that measure in raw minutes. The <a href='/time-card-calculator'>time card calculator</a> takes seven daily entries, totals the week, and multiplies by an hourly rate for a gross-pay estimate. None of them require a login, and none store what you type.
Related tools for values off the chart
Need a value between rows? The <a href='/'>decimal hours calculator</a> converts any hours-and-minutes entry in both directions, and the <a href='/minutes-to-decimal-hours'>minutes page</a> lists every single minute from 1 to 60. For full-week totals with an hourly rate, the <a href='/time-card-calculator'>time card calculator</a> does the arithmetic and estimates gross pay. All three work on mobile and store nothing you type.
A tip worth keeping: the four quarter-hour decimals — .00, .25, .50, .75 — plus the whole hours make up over ninety percent of real timesheet entries. Learn those from this chart and you will rarely need any tool for day-to-day conversions; the calculators are for the long tail and for double-checking.
The calculators also fill the chart's deliberate blind spots. It stops at 12:00 to stay printable on one page, it rounds to whole minutes, and it does not apply rounding policy — it shows truth, and your payroll system shows policy. Where the two disagree by a small, consistent amount, the sections above on rounding rules explain why; where they disagree by more, the calculators help you build the case.