How are working days counted?

The calculator iterates over every calendar day in the range, keeps only the days of the week you selected (e.g. Mon–Fri), then removes any dates you entered as holidays. The remaining count is your total working days.

How do I enter holiday dates?

Paste or type one date per line in the Holidays field using YYYY-MM-DD format (e.g. 2025-12-25). The calculator will exclude any matching dates from the working-day count.

Can I work a partial week, e.g. Mon–Thu only?

Yes. Use the day-of-week checkboxes to select exactly which days count as working days. You can deselect Friday (or any day) for a 4-day working week.

Productivity 無料サインアップ不要

Contract Hours Calculator

Calculate total working days and hours for a contract period.

ツールを読み込み中…

このツールについて

The Contract Hours Calculator helps freelancers and contractors determine the exact number of working days and billable hours in any date range. Set the start and end dates, choose which days of the week you work (Mon–Fri checkboxes), set your daily hours, and optionally paste a list of public holiday dates to exclude. The tool outputs total calendar days, total working days (after removing weekends and holidays), and total contract hours. Perfect for writing accurate statements of work or invoices.

使い方

1 Select a start date and end date for the contract period.
2 Check the days of the week you work (default: Mon–Fri).
3 Enter the number of working hours per day.
4 Optionally paste public holiday dates (one per line, YYYY-MM-DD) to exclude.
5 Click 'Calculate' to see total working days and total contract hours.

Counting working days correctly is harder than it looks

If a contract runs from 1 March to 31 May, how many days are billable? You cannot just subtract the dates, because that counts weekends, and you cannot divide by seven and multiply, because the answer depends on which weekday the range starts and ends on, plus any public holidays. This calculator handles all of that by walking through the date range one day at a time, applying your rules to each day, and tallying the results. The output is total calendar days, total working days, holidays excluded, and total contract hours.

How the day-by-day count works

The tool starts at your start date and steps forward to the end date, inclusive of both ends. For each calendar day it asks two questions:

Is this a working weekday? Only the days you ticked count. By default Monday through Friday are checked and Saturday and Sunday are not, but every day has its own checkbox so you can model any pattern.
Is it a holiday? If the day is a working weekday and its date appears in your holidays list, it is excluded and tallied separately. Otherwise it is counted as a working day.

Total contract hours are then simply working days × hours per day. Because both the start and end dates are included, a single-day contract from 2025-01-01 to 2025-01-01 counts as one day, provided that date is a working weekday.

A worked example

Say you contract from Monday 1 December 2025 to Friday 2 January 2026, working Monday–Friday at 7.5 hours a day, and you exclude three holidays: 2025-12-25, 2025-12-26, and 2026-01-01. The range spans 33 calendar days. Of those, 25 fall on weekdays. Three of the weekdays are holidays you listed, so they drop out, leaving 22 working days. Total hours are 22 × 7.5 = 165. The tool shows: 33 calendar days, 22 working days, 3 holidays excluded, 165 total hours — exactly the numbers you would put on a statement of work.

Entering holidays so they actually count

Holidays must be in ISO format, YYYY-MM-DD, one per line (commas and semicolons also separate them). So 25 December 2025 is 2025-12-25, never 12/25/2025 or 25/12/2025 — anything that does not match the four-two-two pattern is silently ignored. A subtle but important detail: the tool compares dates using your local calendar day, not UTC. That matters if you live east of Greenwich, where a naive conversion could roll a date back to the previous day and cause a holiday to mismatch and fail to be excluded. This calculator avoids that trap, so a holiday you enter is removed on the day you actually observe it.

Modelling non-standard schedules

Four-day weeks. Untick Friday to model a Monday–Thursday schedule. The hours-per-day field is independent, so a 4-day week at 9.5 hours and a 5-day week at 7.6 hours both total 38 hours — but the day counts differ, which affects how holidays land.
Weekend or shift work. Tick Saturday and Sunday and untick weekdays to count a weekend-only pattern, or any custom mix.
Part-days. Hours per day accepts halves (the field steps in 0.5), so a 7.5-hour day is straightforward. For a genuinely irregular schedule, run the tool once per consistent block and add the hours.

Use cases

The calculator is built for freelancers, contractors, and project managers who need defensible numbers rather than guesses:

Quoting a statement of work. Turn a project's start and end dates into a precise billable-hours figure and a day rate that adds up.
Invoicing a fixed period. Confirm how many working days a month or quarter actually contains after public holidays.
Capacity planning. See how many effective working days a team has between now and a deadline.
Holiday-adjusted budgets. Compare two date ranges to see how a holiday-heavy December reduces available hours.

Common mistakes to avoid

Forgetting the end date is inclusive. A 1–7 January range is seven calendar days, not six. If your other system counts exclusively, adjust the end date by one day.
Wrong date format for holidays. A holiday typed as 25-12-2025 will not match and will be counted as a working day. Use YYYY-MM-DD.
Listing a holiday that falls on a non-working day. A holiday on a Sunday you do not work changes nothing — it was already excluded as a non-working weekday, so it will not appear in the holidays-excluded tally.
Leaving every day unticked. At least one working day must be selected, or there is nothing to count.

All calculation happens locally in your browser; no dates or holiday lists are sent anywhere.