Video File Size Calculator
This video file size calculator helps you estimate how much space a video takes up on your disk. All you need to do is select the video and compression format, determine the video length, and choose the frame rate of your file.
If you're unfamiliar with video formats, the calculator can also work out the size of an uncompressed file based on the resolution and color depth — just pick Custom from the format list and type in the width, height, and color depth.
How to calculate the video size
Every video comprises a series of still images, presented one after another to create a moving picture. These still images are called video frames. Each frame is shown on the screen for a very short time (for example, 1/24 of a second), which makes the images appear to blend together.
If you want to calculate the video file size, you need to sum up the data size of each of these digital still images. That means we can find the total file size using:
file size = N × frame size
where N is the number of frames in the video. To find N you need two pieces of information: the duration of the video and its frame rate (the number of frames per second, fps). It usually ranges from 12 fps for animation, through 24 fps for regular movies, to 60 fps and beyond. N is obtained by multiplying these two values, so finally we arrive at:
file size = duration × frame rate × frame size
For an uncompressed frame, the frame size itself is the horizontal resolution H multiplied by the vertical resolution V and the color depth CD (in bits): frame size = H × V × CD. Compressed formats such as H.264 or HEVC pack the same picture into a fraction of that size, which is why this calculator divides by an approximate compression ratio for each codec.
What is the difference between MB and MiB?
If you're not an expert on data size, you're probably perplexed by the conversion between different units. You've undoubtedly heard two contradictory stories: in the first version, one kilobyte is the equivalent of 1000 bytes, and in the second — of 1024 bytes. Which one is true?
The whole confusion stems from mixing up two types of unit prefixes: metric and binary. Metric prefixes always have a numerical value of 10ⁿ (10, 100, 1000, and so on) — milli-, centi-, kilo-, mega-, and giga- are all metric prefixes.
Binary unit prefixes, on the other hand, have a numerical value expressed as a power of two. These are less popular, so you may not have heard of prefixes such as kibi- or mebi-. One kibibyte (KiB) is the equivalent of 1024 bytes, and one mebibyte (MiB) is the same as 1024² bytes.
So what does it mean for our calculator? When using regular metric prefixes and talking about megabytes (MB) or gigabytes (GB), you should use the 1000 multiplier. When you'd rather use kibibytes (KiB) or mebibytes (MiB), you should apply the 1024 multiplier. This calculator always shows both — switch the primary system with the Metric (decimal) / Binary (IEC) toggle.
Is this video space calculator accurate?
Another question you might be asking is about the accuracy of this video file size calculator. Unfortunately, it is not 100% accurate — the actual video size will differ a bit from our computation, because real encoders adapt the bitrate to the content of each scene. Still, you can use this video space calculator to give you an approximate prediction of how much space your new video will occupy on the hard drive.
Frequently Asked Questions
How do I determine the size of a video file?
To estimate the size of an uncompressed video file, follow these steps:
- Multiply the horizontal resolution H by the vertical resolution V and the color depth CD (in bits) to get the size of each frame: frame size = H × V × CD.
- Multiply the frame size by the frame rate (fps) of the video to get the file size per second.
- Multiply this by the total number of seconds in the video's runtime and divide by 8 to get the video file size in bytes.
How many MB is 1 minute of 1080p video?
A minute-long TIFF 1080p 8-bit RGB uncompressed video would occupy about 8958 MB. The frame size is 1920 × 1080 × (3 × 8) = 49,766,400 bits = 6,220,800 bytes ≈ 6.2208 MB. Multiplying by 24 fps and 60 seconds gives 6.2208 × 24 × 60 ≈ 8958 MB. This is exactly the default result of the calculator — try it!
How big is a 4K video file?
It depends heavily on the codec. A raw 4K file is enormous — around 1.76 GB per minute at 24 fps for cinema-grade RAW — while an iPhone shooting 4K ProRes produces roughly 5.5 GB per minute. Everyday H.264 or HEVC 4K clips are far smaller, typically a few hundred megabytes per minute, because those codecs compress the picture aggressively.
Which frame rate should I choose?
24 fps is the cinematic standard, 25 fps is common for PAL television and 30 fps for NTSC, while 48, 50, and 60 fps are used for smooth motion, sports, and gaming. A higher frame rate means more frames per second, so the file grows proportionally — the comparison table shows the size at every common rate at once.