Movie Duration Calculator

A movie duration calculator works out how long a film or video runs from the number of frames it contains and the speed at which those frames play. A moving picture is a stack of still images shown one after another, and the frame rate tells you how many of them appear every second. Divide the total number of frames by the frame rate and you have the running time in seconds. Add credits, transitions or any other extra time and you have the total duration, shown here as hours, minutes and seconds.

Editors, animators and film students use it to check a cut against a target length, to see what a change in frame rate does to the runtime, or to turn a frame count from editing software into a length they can quote. This page also plans your viewing evening: enter a start time, the length of the trailers and the breaks you expect, and the animated timeline shows when each part begins and the clock time you will walk out.

1. Divide the frame count by the frame rate: film seconds = frames ÷ fps.
2. Convert the additional time to seconds. Seconds stay as they are, minutes are multiplied by 60 and hours by 3,600.
3. Add the two: total seconds = film seconds + additional seconds.
4. Split the total into hours (÷ 3,600), then minutes (remainder ÷ 60), then seconds. The calculator drops any fraction of a second when it shows hours:minutes:seconds.
5. For the evening plan, add the trailer minutes and the break minutes to the total, then add that to your start time to get the finish clock time.

A film has 172,800 frames at 24 frames per second. 172,800 ÷ 24 = 7,200 seconds. 7,200 ÷ 3,600 = 2 hours exactly, so the film runs 02:00:00. Add 6 minutes of credits (6 × 60 = 360 seconds) and the total is 7,200 + 360 = 7,560 seconds. 7,560 ÷ 3,600 = 2 hours with 360 seconds left over, and 360 seconds is 6 minutes, so the total is 02:06:00.

Take 180,000 frames. At 25 fps that is 180,000 ÷ 25 = 7,200 seconds, or 2 hours. At 30 fps it is 180,000 ÷ 30 = 6,000 seconds, which is 1 hour 40 minutes. At 24 fps it is 180,000 ÷ 24 = 7,500 seconds, which is 2 hours 5 minutes. The picture content is identical, only the playback speed changes, which is why a higher frame rate gives a shorter film for the same frame count. Another common case is 23.976 fps: 172,800 ÷ 23.976 = 7,207.2 seconds, so the 2-hour film above runs 02:00:07, about seven seconds longer than at exactly 24 fps.

You want to see the 2 hour 6 minute film from example 1 (including credits) starting at 7:30 PM. The cinema shows 15 minutes of trailers and you allow 10 minutes of breaks. The trailers run from 7:30 PM to 7:45 PM. The film proper runs 120 minutes from 7:45 PM to 9:45 PM. The 6 minutes of credits take you to 9:51 PM. Ten minutes of breaks bring you to 10:01 PM. As a check, the total is 15 + 126 + 10 = 151 minutes, which is 2 hours 31 minutes, and 7:30 PM plus 2 hours 31 minutes is 10:01 PM.

• 24 fps: the long-standing standard for cinema films.
• 25 fps: used by PAL broadcast television in many regions.
• 30 fps (and 29.97 fps): used by NTSC television and a lot of online video.
• 50 and 60 fps: smoother motion, common for sport, games and high frame rate video.

The frame breakdown splits your film into up to ten equal segments of frames, so you can see roughly where each tenth of the film starts and how long it lasts. When the frame count does not divide evenly by ten, the last segment is a little shorter. The evening chart shows how many minutes go on trailers, the film, credits and breaks, so you can see at a glance how much of your evening is the film itself.

• Use the exact frame rate from your editing software or file properties, for example 23.976 rather than 24, when precision matters.
• Put credits, title cards and any gaps in the additional time box and pick the right unit.
• For the cinema, add a margin to the trailer time. A listed start time often refers to the adverts, not the film.
• If you only know the film's official running time, multiply its minutes by 60 and by the frame rate to get a frame count, then enter that. For example 105 minutes at 24 fps is 105 × 60 × 24 = 151,200 frames.
• Check the finish time against your last bus, train or babysitter before you book.