Time Calculator

Use Time Calculator to add durations, find elapsed time, and total hours and minutes.

Time Calculator helps you add durations, subtract intervals, and work out the gap between two clock readings. Keep a calculation open while you check the values, then copy the answer or save it as a file. The worksheet keeps your draft on this device so you can return after closing it. 💡 Choose the calculation you need Use Time Calculator for three related tasks. Each mode keeps the input visible beside the result, so you can check what was included. 1. Add or subtract durations written in days, hours, minutes, and seconds. 2. Find the time between two times, with an explicit choice of the same day or the next day. 3. Move a clock reading forward or backward by a duration and see whether it crosses midnight. 📌 Start with your own values Open Time Calculator, choose a mode, and enter the information for that task. You can calculate hours from a single expression or paste a list with one duration per line. - Include a unit after a plain number: 30m means thirty minutes. - Use + and - to combine values; negative durations are accepted. - Select Calculate, or press Ctrl/Cmd+Enter, when the input is ready. Input formats that keep the meaning clear The hours and minutes calculator accepts colon notation as well as unit letters. Units remain d, h, m, and s in every interface language. A decimal point can be used when the value resolves to whole seconds. ➤ 1:30 means one hour and thirty minutes, rather than a clock reading in the duration field. ➤ 0:45:30 includes seconds; 1:90 is rejected because the minutes are out of range. ➤ 1.5h represents ninety minutes. A value smaller than one second is rejected, without rounding it into an accepted input. Try a calculation before replacing a draft Time Calculator includes examples you can load into the worksheet. Replacing nonempty input requires confirmation, giving you a chance to keep the work already entered. 1️⃣ Add 2h 45m and 1h 30m, then subtract 20m: the result is 3:55:00. 2️⃣ Combine 0:45:30 with 1:10:15 to get 1:55:45. 3️⃣ Subtract 4h from 2d to get forty-four hours; totals can exceed twenty-four hours. Check an interval between clock readings As an elapsed time calculator, the second mode uses start and end fields. Enter a 24-hour value such as 21:30, or use 9:15 AM and 5:45 PM. Seconds can also be included. • Choose Same day when both readings belong to the same day. • Choose Next day explicitly for an overnight interval, such as 10 PM to 6 AM. • Equal readings give zero hours on Same day and twenty-four hours on Next day. 📍 Move a starting clock reading The clock calculator mode in Time Calculator adds or subtracts a duration from a starting reading. This is useful when you know an interval and want to determine the resulting hour. ▸ Adding 2h 45m to 11:30 PM gives 2:15 AM, with a shift of one day. ▸ Subtracting 45m from 12:15 AM gives 11:30 PM on the previous day. ▸ The day shift is relative to your input; it is not a calendar date or a time-zone conversion. Read the answer in a useful format Results show a duration breakdown, h:mm:ss, decimal hours, total minutes, and exact seconds. Decimal displays are rounded for readability while arithmetic keeps whole-second precision. Copy the visible result, or export TXT or CSV for use outside the worksheet. Editing an input hides the old answer until you calculate again, so exports cannot silently use a stale result. Return to earlier work Time Calculator saves the current draft and up to twenty recent distinct successful calculations locally. Select a history entry to restore its inputs and review it again. Repeating the same calculation does not fill the history with duplicates. Clear inputs and Clear history are separate actions; deleting all local data requires confirmation. Wait for the saved status before closing the tab. Bring in a selected expression You can open the extension from its icon or its page context menu. A separate action offers selected text for import. Review that text before applying it: importing never silently replaces the current expression. The tool does not scan a page for durations or automatically record activity. If a page does not offer the menu, open the worksheet and paste the values yourself. Use the interface in your language The extension includes fifty-two interface languages, automatic browser-language detection, and a language selector whose choice is saved locally. Switching languages preserves the current inputs and answers. Right-to-left layouts are available where appropriate; calculation syntax stays the same across languages. Questions and boundaries Can this be used as a time difference calculator for dates in different zones? No. It works with clock readings and explicit day choices, without calendar dates, named time zones, or daylight-saving adjustments. Does the duration calculator compute pay or track attendance? No. It does not calculate wages, apply break rules, run a timer, or monitor activity. There is no multiplication, division, or audio-frame conversion. Local work and practical limits Time Calculator works offline without an account or cloud synchronization. Drafts and history stay on this device; uninstalling removes the extension's stored data, so export what you need first. Clipboard content and downloaded files are not removed by deleting local data. A worksheet accepts up to five hundred lines and fifty thousand characters, with the sum of absolute duration terms limited to one million days.