Creative Tools
Video Bitrate Calculator
Enter bitrate and length to see approximate file size.
How big will my video file be?
Video file size is driven mainly by bitrate and duration: a higher megabits-per-second (Mbps) encode looks sharper but fills disks and upload quotas faster. Approximate megabytes ≈ video Mbps × duration in seconds ÷ 8, then add audio (kilobits per second, kbps) the same way. Streaming sites often re-encode after upload, but your source still has to fit their size or length caps. Variable bitrate (VBR) oscillates around the average, so treat the result as a planning figure. When you already know a size budget, invert the problem with the video file size to bitrate calculator.
Worked example
8 Mbps for 12 minutes (720 s) → 720 MB of video. Audio at 128 kbps adds ≈ 11.5 MB → about 731.5 MB total (~61 MB per minute).
Limits and assumptions
Ignores container overhead and VBR peaks. HDR and high frame-rate masters often need higher bitrates than this sketch.
Frequently asked questions
What is Mbps versus MB?
Mbps is megabits per second (data rate). There are 8 bits in a byte, so divide megabits by 8 to get megabytes.
What bitrate should I use for 4K?
Often several times a 1080p rate for the same codec and quality target — check your encoder’s delivery presets.
Why enter audio kbps separately?
Spoken-word tracks are small next to video, but podcasts with simple picture still need the audio term for a honest total.
Master versus streaming upload?
Masters are larger and cleaner; platforms transcode for viewers. Size limits usually apply to what you upload.