Every frame of digital video is an image, and before compression its size is fixed by three numbers: how many pixels wide, how many tall, and how many bits describe each pixel. A Full HD frame at 24-bit colour is 1920 × 1080 × 3 = 6.2 MB; at 30 frames per second that is 187 MB every second, or 1.49 gigabits per second – far more than any phone or streaming service could handle.
Knowing the raw frame size helps in many places: choosing capture cards and SDI links, sizing frame buffers in video software, estimating image-sequence storage for VFX, or understanding how hard a codec works. YouTube’s recommended 8 Mbit/s for 1080p30 means squeezing the raw 1,493 Mbit/s by a factor of about 187.
Colour depth here means bits per pixel. 24-bit RGB stores 8 bits for each of red, green and blue; 8-bit video in 4:2:2 chroma subsampling needs 16 bits per pixel and 4:2:0 only 12, while 10-bit and 16-bit formats for grading need more.
How to use the Video Frame Size Calculator
- Horizontal pixels
- Vertical pixels
- Colour depth
- Frame rate
- Video length
- Target bitrate (for the compression ratio)
Results update as you type, every field has its own unit menu, and everything is calculated in your browser.
How it works
Enter the resolution, choose the colour depth (bits per pixel), the frame rate and the clip length. One frame is width × height × bits ÷ 8 bytes; multiply by frames per second and by seconds for the clip, and divide the raw bitrate by your target bitrate to see the compression a codec must achieve.
Worked example
A 1920 × 1080 frame at 24-bit colour is 1,920 × 1,080 × 24 ÷ 8 = 6,220,800 bytes (6.22 MB). At 30 fps one minute has 1,800 frames, so the clip takes 6,220,800 × 1,800 = 11.2 GB (11,197,440,000 bytes) uncompressed, at 1,492.99 Mbit/s. To stream it at 8 Mbit/s a codec must compress about 186.6 : 1, giving a 60 MB file.
Uncompressed frame sizes at 24-bit colour
| Resolution | Pixels | One frame | Per second at 30 fps |
|---|---|---|---|
| 640 × 480 | 307,200 | 0.92 MB | 27.6 MB |
| 1280 × 720 | 921,600 | 2.76 MB | 82.9 MB |
| 1920 × 1080 | 2,073,600 | 6.22 MB | 186.6 MB |
| 3840 × 2160 | 8,294,400 | 24.88 MB | 746.5 MB |
| 7680 × 4320 | 33,177,600 | 99.53 MB | 2,986 MB |
Inputs explained
| Field | What to enter |
|---|---|
| Horizontal pixels | A number |
| Vertical pixels | A number |
| Colour depth | Choose one: 8-bit (256 colours, 1 byte per pixel), 12-bit (8-bit YUV 4:2:0), 16-bit (high colour, or 8-bit 4:2:2), 24-bit (true colour RGB) … |
| Frame rate | In fps |
| Video length | Units: min, s, h |
| Target bitrate (for the compression ratio) | Units: Mbit/s, Gbit/s, kbit/s, bit/s, MB/s, GB/s … |
What each result means
- One frame size = [Horizontal pixels]×[Vertical pixels]×[Colour depth]÷8
- Total video size (uncompressed) = [One frame size]×[Frame rate]×[Video length]
- Uncompressed bitrate = [Horizontal pixels]×[Vertical pixels]×[Colour depth]×[Frame rate]
- Number of frames = [Frame rate]×[Video length]
- Pixels per frame = [Horizontal pixels]×[Vertical pixels]
- Size per minute = [One frame size]×[Frame rate]×60
- Compression ratio needed for the target bitrate = [Uncompressed bitrate]÷[Target bitrate (for the compression ratio)]
- Clip size at the target bitrate = [Target bitrate (for the compression ratio)]×[Video length]÷8
Formula
Frame size (bytes) = horizontal px × vertical px × colour depth (bits) ÷ 8 · Video size = frame size × frame rate × time · Raw bitrate = frame size × 8 × frame rate · Compression ratio = raw bitrate ÷ target bitrate
Worked example
Inputs — Horizontal pixels: 1,920; Vertical pixels: 1,080; Colour depth: 24-bit (true colour RGB); Frame rate: 30 fps; Video length: 1 min; Target bitrate (for the compression ratio): 8 Mbit/s.
Results — One frame size = 6.221 MB; Total video size (uncompressed) = 11,197.44 MB; Uncompressed bitrate = 1,492.99 Mbit/s; Number of frames = 1,800; Pixels per frame = 2,073,600; Size per minute = 11,197.44 MB; Compression ratio needed for the target bitrate = 186.6 : 1; Clip size at the target bitrate = 60 MB.
Key terms
- Frame size
- Storage needed for one uncompressed frame.
- Colour depth
- Bits used to describe the colour of one pixel.
- Chroma subsampling
- Storing colour at reduced resolution (4:2:2, 4:2:0) to save space.
- Compression ratio
- Raw data rate divided by compressed data rate.
Frequently asked questions
How big is one 1080p frame?
1920 × 1080 × 24 bits ÷ 8 = 6,220,800 bytes (6.22 MB) in RGB; 4,147,200 bytes in 8-bit 4:2:2.
How big is one 4K frame?
3840 × 2160 × 3 bytes = 24.9 MB at 24-bit colour.
How much data is uncompressed 1080p30 per second?
6.22 MB × 30 = 186.6 MB/s, or about 1.49 Gbit/s.
What does colour depth mean in video?
The number of bits per pixel. 24-bit stores 8 bits per RGB channel (16.7 million colours); 30-bit stores 10 bits per channel (1.07 billion).
How much is 640 × 480 at 24-bit, 30 fps?
921,600 bytes per frame, about 27.6 MB per second.
Why are real video files so much smaller?
Codecs remove redundancy within and between frames; H.264 at streaming bitrates is typically 100–200 times smaller than raw video.