Time & DateUpdated May 2026

Time Calculator

Add, subtract, multiply, or divide time in hours, minutes, and seconds. Convert between time formats instantly.

100% Free
No Signup
Works Offline
Updated 2026

Time Calculator

Use this free time calculator to add, subtract, multiply, or divide hours, minutes, and seconds.
Hours : Minutes : Seconds
Hours
Minutes
Seconds
About Time Calculations

Time calculations help you add or subtract time periods for various applications.

Common Uses:

  • Work Schedules: Calculate shift durations and breaks
  • Travel Planning: Add travel time to departure times
  • Cooking: Recipe timing and meal preparation
  • Sports: Race times and performance tracking

Time Conversion:

  • 1 hour = 60 minutes = 3,600 seconds
  • 1 minute = 60 seconds
  • 1 day = 24 hours = 1,440 minutes

Calculation Tips:

  • Results automatically handle carry-over (e.g., 90 minutes = 1 hour 30 minutes)
  • Negative results indicate times before the start time
  • Use for precise timing beyond simple clock arithmetic
  • Helpful for calculating durations and elapsed time

This calculator works with 24-hour time format and handles time arithmetic across day boundaries.

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How our time calculator works

1

Enter two times

Type start and end times using hours, minutes, and seconds. The calculator accepts both 12-hour (AM/PM) and 24-hour formats.

2

Add or subtract duration

Choose to add a duration (e.g. 2h 30m) to a starting time, or subtract a duration to find the earlier time. We handle day rollover automatically.

3

Get the result in multiple units

See the answer in hours, minutes, seconds, decimal hours, and total seconds. Perfect for payroll, billing, and time tracking.

Key things to know about our time calculator:

  • Decimal hours: This is how payroll and invoicing software bill time: 7h 30m = 7.50 decimal hours.
  • Multi-day math: For time tracking across days, pair with our hours calculator or date duration calculator.
  • Format conversion: Use the time calculator to convert between time formats instantly without doing the math by hand.

For related calculations, try our hours calculator.

Verified accuracy

Cross-checked against authoritative formulas (IRS, NIST, ACM) and updated for 2025/2026 tax years and rates.

Instant results

No server roundtrip. All math runs in your browser so results appear the moment you finish typing.

Your data stays private

We never collect, store, or transmit your inputs. Every calculation runs locally in your browser.

Learn as you calculate

Each calculator includes the formula, plain-English explanation, and FAQs so you understand the result.

Estimates only. Calculator results are for educational and planning purposes — not professional advice. For binding decisions on taxes, investments, health, or legal matters, consult a qualified professional.

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