SixtySum - Time Calculator

Add hours, minutes & seconds

Only for iPhone

Free · Designed for iPhone. Not verified for macOS.

iPhone

Built for editors, streamers, and crews who add up hours, minutes, and seconds all day. Tap H/M/S, type, done. No ads, no login, fully offline. Time isn't decimal. Your calculator shouldn't be either. SixtySum is a calculator built for one job: adding and subtracting hours, minutes, and seconds — fast. A regular calculator works in tens. Time works in sixties. SixtySum does the base-60 math for you, so 50 minutes plus 20 minutes is 1 hour 10 minutes — not 70. Tap H, M, or S, type the numbers, and go. No colon to fumble with. No menus to dig through. No internet to wait for. WHO IT'S FOR Video editors, streamers, audio and stage crews, and anyone who works by the clock and needs the total now — not after another web search. WHAT YOU CAN DO - Add and subtract HH:MM:SS values - Switch instantly between H / M / S input - Drop in 15m / 30m / 45m with a single tap - Chain calculations without stopping - See negative results for time differences - Review your last 20 calculations at a glance QUIET BY DESIGN - One-time purchase — buy it once, keep it - No ads - No subscription - No login or account - No tracking - Works fully offline SixtySum stays out of your way and just gives you the number. Note: Calculation history is kept for the current session only and is not saved permanently.

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Add the Japanese store description

Version 1.0.1

The developer, KENTA OSAWA, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .

  • Data Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    Accessibility

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Information

    Seller
    KENTA OSAWA
    Size
    16.1 MB
    Category
    Utilities
    Compatibility
    Requires iOS 15.0 or later.
    • iPhone
      Requires iOS 15.0 or later.
    • iPod touch
      Requires iOS 15.0 or later.
    • Mac
      Requires macOS 12.0 or later and a Mac with Apple M1 chip or later.
    • Apple Vision
      Requires visionOS 1.0 or later.
    Languages
    English
    Age Rating
    4+
    Copyright
    © 2026 K's App
  • Privacy Policy

    • More by KENTA OSAWA

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