Calculate your hours effortlessly: enter times, sum intervals, and rely on automatic adjustments for greater accuracy.
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History
The hour calculator allows you to accurately measure the time between two dates and, optionally, between times (HH:MM). You can consider only business days, apply holidays (manual/assisted), include or exclude the end date, display weeks, convert the result into hours based on "Hours per day," and even estimate the corresponding percentage of the year—all locally, right in your browser, and without registration.
Unlike manual spreadsheets, the tool automates rules like inclusion/exclusion of weekends, leap years, and the inclusion of the end date. It also offers fine adjustments (non-working/compensated days) to tailor the total to your real-world context.
How to Use the Calculator (Step-by-Step)
Set the interval: select a Start Date and End Date. Use the "Today" shortcuts for speed.
Include times (optional): enable Include times (HH:MM) and fill in Start Time and End Time for greater intraday precision.
Choose your options: check Include end date, Exclude weekends, Show weeks, Total in hours, and % of a year as needed.
Holidays: enable Apply holidays and enter the number of holidays within the interval (supports fractions, e.g., 1.5).
Fine adjustments: use Non-working days, Compensated days, and adjust Hours per day (e.g., 8h) to reflect your workday.
Calculate and review: click Calculate, check the result, and open Details ▾ for a technical summary of what was applied.
Export and history: use Copy days / Copy summary and Save to History for later reuse.
Application Features (Highlights)
End date inclusion: control whether the last day is counted (changes the total by 1 day).
Business vs. calendar days: enable Exclude weekends to get the net working period.
Configurable holidays: deduct holidays (working days) by entering an integer or fractional number.
Weeks and % of year: view the interval in weeks (and remaining days) and as a fraction of the year.
Total in hours: convert final business days into hours based on Hours per day.
Details and badges: a details panel and quick "badges" show the active rules.
Local history and copy: save calculations and copy results for reports and spreadsheets.
Privacy by default: everything is processed locally; no data is sent to servers.
Responsive and accessible: great readability on mobile/desktop, with messages via aria-live.
Understanding Outputs and Metrics
Calendar days: total days between dates (with or without including the end date).
Net business days: calendar days minus weekends and holidays, plus/minus adjustments.
Weeks: broken down into W weeks + D days for quick reference.
Total in hours:final business days × Hours per day (configurable value).
% of a year: approximate fraction of the calendar year based on the total calendar days selected.
Technical details: lists what was checked (inclusive, weekends, holidays, adjustments, hours/day).
Customization and Common Workflows
Adapt the options to your work or study context:
Part-time schedule: set a lower Hours per day (e.g., 6h) for internships/part-time jobs.
Extended shifts: use 10–12h/day (where applicable) for on-call duties and special regimes.
Consistent rules: maintain the same policy (inclusive/exclusive) when comparing periods.
Local holidays: adjust the number according to your city/country and re-evaluate when changing dates.
Accessibility and Cross-Device Use
Status messages: results and warnings use aria-live regions for screen readers.
Keyboard navigation: fields and buttons have a logical order and visible focus.
Compatibility: works well on modern browsers; after loading, it continues to operate offline (local resources).
Best Practices
Define the policy first: deciding on end date inclusion avoids rework.
Combine filters wisely: "Exclude weekends" + "Apply holidays" approximates the real business day count.
Review holidays when changing dates: reopen the option to check the entered number.
Document criteria: when sharing results, state the options used for transparency.
Common Errors to Avoid
Inverting dates: unintentionally setting "End Date" before "Start Date".
Double-counting deductions: excluding weekends and then manually subtracting the same days.
Inconsistent holidays: entering a number that doesn't match your locality.
Changing rules mid-comparison: toggling end date inclusion during comparisons distorts results.
Unrealistic hours per day: setting 0h or values incompatible with your scenario.
When to Use "Adjustments"?
Use Non-working days to deduct one-off absences (vacations, leaves, office closures) and Compensated days to add back extra work events (team efforts, additional shifts). Adjust Hours per day to ensure the hour calculation reflects your actual workday.
Frequently Asked Questions (FAQ)
Does counting the same date give 0 or 1 day? With Include end date, it counts as 1; otherwise, 0.
What about leap years? They are automatically considered (Feb 29) when present in the interval.
Does the total in hours change with "Hours per day"? Yes. It's an estimate based on your configured workday.
Can I use it offline? Yes, after the page has loaded (local resources).
Is my data sent anywhere? No. Everything stays in your browser; the history is local.
Summary
The hour calculator provides a complete view of the period between dates and times, with control over business days, holidays, and adjustments. Export, save history, and maintain clear criteria for consistent comparisons—simple, precise, and private.
Note: educational content; does not substitute legal, medical, or professional advice. Adapt practices to your context, local rules, and needs.