The spreadsheet is where most people’s own hours end up, and it deserves better than it usually gets: it is a perfectly good record with one specific arithmetic failure and one specific practical one. Worth knowing both before deciding whether to replace it.
A time tracking spreadsheet is a legitimate record. The US Department of Labor requires no particular form for hours records, and neither the IRS nor GOV.UK sets rules about record format. It fails in two places: clock time typed into a cell is base 60 while the cell does base 10, and the file gets filled in afterward.
Both of those are fixable, and neither is the reason people abandon the file in March. Worth taking them in order.
Is a spreadsheet an acceptable record at all?
Yes, and this is worth stating first because it is the thing the download pages never say. The US Department of Labor’s recordkeeping fact sheet for the Fair Labor Standards Act states that the Act “requires no particular form for the records” as long as they contain the required information about hours worked and wages earned, and that employers “may use any timekeeping method they choose”, adding that “any timekeeping plan is acceptable as long as it is complete and accurate”. That is a US employer obligation rather than a rule about your own file, but it establishes the standard: the medium does not matter, completeness and accuracy do.
For the self-employed the same principle appears in both jurisdictions. The Internal Revenue Service tells US small businesses and self-employed filers that, except in a few cases, the law does not require any special kind of records, only that they clearly show income and expenses. In the United Kingdom, GOV.UK’s guidance on keeping pay and tax records states that “there are no rules on how you must keep records” and that “you can keep them on paper, digitally or as part of a software program (like book-keeping software)”, while warning that HMRC can charge a penalty if records are not accurate, complete and readable.
So nobody is going to reject your spreadsheet for being a spreadsheet. The problems are internal to it.
What is the arithmetic failure?
Clock time is base 60 and arithmetic is base 10, and nothing warns you when the two get mixed. A spreadsheet handed a genuine time value will handle it correctly. The trouble is what gets typed. A duration read off a clock as seven forty-five is very often entered as 7.45, and 7.45 hours is not seven hours and forty-five minutes, it is seven hours and twenty-seven minutes, because 0.45 times 60 is 27.
Worked in full: 7 hours 45 minutes plus 6 hours 30 minutes is 14 hours 15 minutes, which is 14.25 in decimal hours because 15 divided by 60 is 0.25. Read the same two entries as the decimals 7.45 and 6.30 and you get 13.75. The gap is exactly half an hour across two entries, and it is invisible, because 13.75 is a plausible number.
The conversion itself is not hard. Divide the minutes by 60 and add: 45 divided by 60 is 0.75, so 7:45 is 7.75. North Carolina’s Department of Labor publishes the full minute-by-minute chart, and Duke University’s payroll office publishes the tenths-of-an-hour version, which rounds each minute to the nearest tenth instead. Those two charts disagree at the edges by design, which is a good reminder that a rounding convention is a choice rather than a fact. Decimal hours sets the conversion out properly, and the hours calculator will do a start time, a finish time and a break without any of this.
What does a correct week look like?
Here is one week entered the safe way, with clock time kept in one column and decimal hours in another. The figures are an example, not measured data. Every decimal is the elapsed time in minutes divided by 60.
| Day | Start | End | Break | Worked | Decimal |
|---|---|---|---|---|---|
| Monday | 9:00 | 17:30 | 0:45 | 7:45 | 7.75 |
| Tuesday | 8:45 | 16:15 | 0:30 | 7:00 | 7.00 |
| Wednesday | 9:15 | 18:00 | 1:00 | 7:45 | 7.75 |
| Thursday | 9:00 | 15:40 | 0:20 | 6:20 | 6.33 |
| Friday | 10:00 | 17:10 | 0:45 | 6:25 | 6.42 |
Monday is 9:00 to 17:30, which is 8 hours 30 minutes, less a 45-minute break, so 7:45, and 45 divided by 60 is 0.75. Thursday is 6 hours 40 minutes elapsed less 20 minutes, so 6:20, and 20 divided by 60 is 0.3333, shown as 6.33.
The totals: 465 plus 420 plus 465 plus 380 plus 385 minutes is 2,115 minutes, which is 35 hours 15 minutes, or 35.25 hours. Adding the rounded decimal column gives 7.75 plus 7.00 plus 7.75 plus 6.33 plus 6.42, which is 35.25 as well. The rounding cost nothing this particular week, but it will not always: twenty minutes is exactly one third of an hour, so writing it as 0.33 rather than 0.3333 loses 0.0033 hours each time, and fifty such entries across a quarter lose 50 x 0.0033, which is 0.167 hours, or about 10 minutes. Small, but only if you know it is there. A ready-made grid with the formulas already in it is in the timesheet template guide.
What is the practical failure?
The file is not open when the work happens. That is the whole of it, and it is why the arithmetic above is the smaller problem.
A spreadsheet is filled in at a moment chosen for convenience, which in practice means Friday afternoon, or the day the invoice is due. By then the week is being reconstructed rather than recorded, and reconstruction is a different operation from measurement. It does not fail loudly. It produces a tidy grid of round numbers, 2 hours here and 1.5 there, which is the signature of a week remembered in halves rather than one that happened in fragments of 25 and 40 minutes. Freelance time tracking covers what that costs when the grid becomes an invoice line. What a log has to capture while the work is still happening is covered in keeping a work log that is still accurate on Friday.
The other practical cost is switching. A spreadsheet entry takes several decisions: which row, which columns, what to call the work, and what the elapsed time was. Four decisions is not much once. It is a great deal at eleven in the morning when the thing you were doing has just been interrupted. What a tracker with fewer decisions per entry looks like is covered in simple time tracker.
Paper, spreadsheet or a running timer?
Judged on what each one costs in attention and what each one loses, rather than on a score.
| Paper log | Spreadsheet | Running timer | |
|---|---|---|---|
| Cost of one entry | write a line, if the page is there | open the file, find the row, type four fields | one tap |
| Where the arithmetic happens | in your head or a calculator | in formulas you wrote | it is already the elapsed time |
| Characteristic failure | the notebook is in the other room | clock time typed as a decimal, and Friday reconstruction | you forget to switch, so one activity absorbs the next |
| What you have after a month | a stack of pages to add up | a column you can sort, filter and total | totals already grouped by activity |
| Survives a genuinely busy week | only if it stays on the desk | rarely, because it is written afterward | yes, if switching is a single action |
Each column wins something real. Paper is the only one that works with no device and no battery, and writing by hand is a decent aid to remembering the day. The spreadsheet is the only one that lets you restructure the data afterward, sort by client, filter a quarter, or run a formula you thought of later, and it is the only one you can hand to someone else in a format they already have. A timer is the only one that records the hours at the moment they pass.
How to choose based on how your own week goes
If your week is a small number of long blocks, two or three clients, whole mornings at a time, a spreadsheet is genuinely fine. There is little to forget and the entries are few. Fix the decimal column, keep the file where you will actually open it, and stop reading articles about tracking software.
If your week is fragmented, six or seven switches a day, the spreadsheet will not lose the arithmetic, it will lose the switches, and no amount of formula work fixes that. What you need is a record made at the moment rather than after it.
That is the step Timeness covers and the only one it covers. Make an activity per client or per piece of work, tap once to start and once to switch, and the day timeline plus the week, month and year donut charts add up what actually happened. Everything is on the device with private iCloud sync and there is no account to make. The spreadsheet does not have to go away: the day timeline gives you the start and end times to copy into it, except that the numbers you copy were recorded rather than remembered.
Whichever you pick, the test is the same one: at the end of a month, can you say where the hours went without guessing? Run a time audit for one week in whichever tool you already have and the answer will be obvious.
Sources
- US Department of Labor Fact Sheet 21: Recordkeeping Requirements Under the Fair Labor Standards Act
- Internal Revenue Service: Recordkeeping for small businesses and the self-employed
- GOV.UK: Keeping your pay and tax records
- North Carolina Department of Labor: Time Conversion Chart, Minutes to Decimal Hours
- Duke University Finance: Chart to Convert Minutes to Tenths of an Hour