Free calculator
Film Footage to Time Calculator
A 400 ft roll of 35mm 4-perf runs 4 minutes 27 seconds at 24 fps; 400 ft of Super 16 runs 11 minutes 7 seconds. Enter a roll length to get its running time, or a runtime to get the feet of stock it needs, for ten formats from Super 8 to 15-perf IMAX.
Free, no sign-up. Runs in your browser.
This web tool counts rolls against the roll you have loaded and accepts fractional frame rates such as 23.976. Save, share and get the Pro tools in the app.
How it works
frames = ⌊feet × frames per foot⌋ runtime = frames ÷ fpsA partial frame at the end of the roll is not counted. The runtime shown is rounded to the nearest second, with the exact seconds underneath. Meters are converted at 3.28084 ft per meter.
Where
- frames per foot
- Super 8 72, Super 16 40, 35mm 2-perf 32, 3-perf 21⅓, 4-perf 16, VistaVision 8, 65mm 5-perf 12.8, 8-perf 8, 10-perf 6.4, IMAX 15-perf 4.267
- fps
- camera frame rate(fps)
feet = seconds × fps ÷ frames per footFeet + frames splits the answer the way a footage counter reads it. The roll count divides by the roll you load and rounds up; order extra for slates, run-ups and retakes.
frames per foot = 64 ÷ perforations per frame35mm and 65mm film both have 64 perforations per foot, so 4-perf 35mm gets 16 frames a foot and 15-perf IMAX gets 64 ÷ 15 = 4.267. Super 8 and Super 16 run at 72 and 40 frames per foot.
Rounding and rolls
Runtimes round to the nearest second, as the CineMath app shows them, so 666.67 seconds reads 11:07 where Kodak's charts truncate to 11 min 06 sec; the exact seconds are in the result. In Runtime → Footage, choose the roll you load for the roll count. It starts at the CineMath app's default roll for the format: 50 ft for Super 8, 400 ft for Super 16 and 1,000 ft for 35mm and 65mm.
Worked example
A 400 ft roll of Super 16 at 24 fps, and stock for 30 minutes of 3-perf
- 400 ft × 40 frames/ft = 16,000 frames
- 16,000 ÷ 24 fps = 666.67 s → 11:07
- 30 min × 60 × 24 fps = 43,200 frames
- 43,200 ÷ 21.333 frames/ft = 2,025 ft → 3 rolls of 1,000 ft
400 ft of Super 16 lasts 11 min 7 s at 24 fps; 30 minutes of 3-perf 35mm needs 2,025 ft.
Quick reference
Frames per foot and running time at 24 fps
| Format | Frames/ft | Feet/min | 400 ft | 1,000 ft |
|---|---|---|---|---|
| Super 8mm | 72 | 20 | 20:00 | 50:00 |
| Super 16mm | 40 | 36 | 11:07 | 27:47 |
| 35mm (2-perf) | 32 | 45 | 8:53 | 22:13 |
| 35mm (3-perf) | 21.33 | 67.5 | 5:56 | 14:49 |
| 35mm (4-perf) | 16 | 90 | 4:27 | 11:07 |
| 35mm (8-perf VistaVision) | 8 | 180 | 2:13 | 5:33 |
| 65/70mm (5-perf) | 12.8 | 112.5 | 3:33 | 8:53 |
| 65/70mm (8-perf) | 8 | 180 | 2:13 | 5:33 |
| 65/70mm (10-perf) | 6.4 | 225 | 1:47 | 4:27 |
| 65/70mm IMAX (15-perf) | 4.27 | 337.5 | 1:11 | 2:58 |
Save, share and get the Pro tools in the CineMath app
CineMath is a free download for iPhone, iPad and Mac, with this calculator built in. In version 1.3, coming soon to the App Store, CineMath Professional saves calculations to your history, shares them as links, and adds the Camera Database and Data Planning.
Questions
How many feet of film per minute?
At 24 fps: 90 ft a minute for 35mm 4-perf, 67.5 for 3-perf, 45 for 2-perf, 36 for 16mm and Super 16, 20 for Super 8 (15 at 18 fps), 112.5 for 65mm 5-perf and 337.5 for 15-perf IMAX. Multiply by fps ÷ 24 for other rates: 4-perf at 48 fps uses 180 ft a minute.
How long is a 400 ft roll of 16mm film?
11 minutes 7 seconds at 24 fps: 400 ft × 40 frames = 16,000 frames, and 16,000 ÷ 24 = 666.67 seconds. At 25 fps it is 10 minutes 40 seconds. Kodak lists the 24 fps figure as 11 min 06 sec because it drops the fraction instead of rounding.
How long is a 1,000 ft roll of 35mm?
At 24 fps: 11 minutes 7 seconds in 4-perf, 14 minutes 49 seconds in 3-perf and 22 minutes 13 seconds in 2-perf. Fewer perforations per frame means more frames per foot, so the same roll lasts longer.
How much film stock do I need?
Work out the screen time you will shoot, then multiply by your shooting ratio. Ninety minutes of 4-perf at 24 fps is 8,100 ft of finished film; at a 10:1 shooting ratio that is 81,000 ft of stock. Choose Runtime → Footage and enter the total running time you plan to expose.
How many frames are in a foot of film?
16 for 35mm 4-perf, 21⅓ for 3-perf, 32 for 2-perf, 40 for 16mm and Super 16, 72 for Super 8, 12.8 for 65mm 5-perf and 64 ÷ 15 ≈ 4.27 for 15-perf IMAX. The calculator keeps 21⅓ and 64 ÷ 15 as fractions, so 1,000 ft of IMAX is 4,266 frames, not 4,270.
How do I convert film meters to feet?
Multiply meters by 3.28084 to get feet, or multiply feet by 0.3048 to get meters. A 122 m roll is about 400 ft (400.26 ft) and 305 m is about 1,000 ft. Choose Meters next to the roll length and the calculator converts for you.