Timesheet Calculator
Paste a work log of start–stop times tagged by project and instantly total the hours per project and the billable amount. Handles am/pm and overnight shifts, per-project rates, and 6-minute (0.1h) rounding — all in your browser, nothing uploaded.
About this tool
The Timesheet Calculator turns a plain-text work log into a costed timesheet. Write one entry per line as a start–stop time range, tag it with a project, and the tool totals the hours for each project and multiplies them by your hourly rate to get the billable amount. It runs entirely in your browser — your log never leaves your device.
Each line follows a simple, forgiving format:
[YYYY-MM-DD] START-END PROJECT [notes]
- Times can be 24-hour (
9:00,17:15) or 12-hour with am/pm (9am,5:30pm). - Overnight shifts are handled automatically: if the end is earlier than the start, the entry
rolls past midnight —
22:00-02:00is 4 hours. - The project/tag is the word right after the time range; a leading
#is stripped, so#AcmeandAcmeare the same project. Anything after the project is kept as notes. - Lines that are blank or start with
#or//are treated as comments and skipped. - An optional date at the start of the line is recorded but does not affect the totals.
Worked example
Log (default rate 100, currency $, no rounding):
9:00-12:30 Acme kickoff call
13:00-17:15 Acme build feature
2024-01-15 10:00-11:00 #Beta review
Result (abridged JSON):
{
"projects": [
{ "project": "Acme", "minutes": 465, "hours": 7.75, "rate": 100.0, "amount": 775.0 },
{ "project": "Beta", "minutes": 60, "hours": 1.0, "rate": 100.0, "amount": 100.0 }
],
"total_minutes": 525,
"total_hours": 8.75,
"total_amount": 875.0,
"summary": "3 entries across 2 project(s) · 8.75 h · $875.00"
}
Acme's two blocks (3 h 30 m + 4 h 15 m) total 7 h 45 m = 7.75 h → $775; Beta's single hour → $100; the grand total is 8.75 h and $875.
Rates and rounding
Set a single default hourly rate, or give per-project overrides in the Per-project rate
overrides field as Project=amount pairs (Acme=150, Beta=90) — any project not listed falls back
to the default. Choose a rounding increment to bill in whole blocks: 6 minutes is the
tenth-of-an-hour standard used in legal billing, and 15/30/60 minutes are common in payroll.
Each entry's duration is rounded to the nearest multiple before it is costed.
FAQ
What time formats does the work log accept?
Times can be written 24-hour (9:00, 13:45, 17:15) or 12-hour with a meridiem (9am, 1pm,
5:30pm). A bare hour like 9am is treated as 9:00. Each entry is a START-END range with no
space inside the range token, for example 9:00-12:30 or 8am-4:30pm.
How are overnight or past-midnight shifts handled?
If the end time is earlier than the start time, the tool assumes the entry crosses midnight and adds
24 hours. So 22:00-02:00 and 10pm-2am both come out to 4 hours. This means a single entry can be
at most 24 hours long.
What is the 6-minute rounding option?
Six minutes is one tenth of an hour (0.1 h), the standard billing increment used by many law firms
and agencies. With 6 minutes selected, a 4-minute entry rounds up to 6 minutes (0.1 h) and a
1 h 5 m entry rounds to 1 h 6 m (1.1 h). Rounding is applied to each entry's duration (to the
nearest multiple, ties rounding up) before the amount is calculated. Pick No rounding to bill
the exact minutes.
Can different projects have different rates?
Yes. Put a default hourly rate in the Default hourly rate field, then add overrides in the
Per-project rate overrides field as Project=amount pairs separated by commas or new lines — for
example Acme=150, Beta=90. Any project you do not list uses the default rate. Leave the rate at 0
to total hours only, with no money.
Is my timesheet uploaded anywhere?
No. All parsing and arithmetic run locally in your browser via WebAssembly. Nothing you paste is sent to a server, so it is safe for confidential client and payroll data.
What are the limits and edge cases?
Minutes must be 00–59 and 24-hour hours 0–23 (12-hour hours 1–12). A line with no
recognizable START-END range, or an out-of-range time, is reported as an error naming the line
number. A line with no project token is grouped under (no project). The date prefix is optional and
only recorded — totals are computed purely from the time ranges, so entries on different dates with
the same project are still summed together.
Developer & Automation Access
Run it from the terminal
Same engine as this page, headless — via the gizza CLI:
gizza tool timesheet-calculator "9:00-12:30 Acme kickoff call
13:00-17:15 Acme build feature
2024-01-15 10:00-11:00 #Beta review"New to the CLI? Get gizza →
Open it by URL
Pre-fill and auto-run this tool with query parameters — the names match the API/CLI:
https://gizza.ai/tools/timesheet-calculator/?log=9%3A00-12%3A30%20Acme%20kickoff%20call%0A13%3A00-17%3A15%20Acme%20build%20feature%0A2024-01-15%2010%3A00-11%3A00%20%23Beta%20review&rate=100&rates=Acme%3D150%2C%20Beta%3D90¤cy=%24&round=0Machine-readable descriptor: tool.json — title + parameters JSON Schema for agents.