Video Bitrate Calculator

How the video bitrate calculator works

Bitrate, duration, and file size are three sides of one equation. Fix any two and the third is determined. This calculator exposes that identity directly so you can solve in whichever direction you need, with the arithmetic shown for every result.

The core formula is file size (MB) = bitrate (Mbps) × duration (s) ÷ 8, where the divide-by-8 converts bits to bytes. Rearrange it to solve in any direction: bitrate = size × 8 ÷ duration for the bitrate, or duration = size × 8 ÷ bitrate for the playable length.

Audio counts too. When you enable an audio track, the calculator adds its bitrate (stereo defaults to 384 kbps) to the video bitrate before computing size. That matches how a real muxed file works — the container carries both streams, and both consume your data budget.

Why bitrate matters for AI video and uploads

Bitrate is the data budget per second of video. More bits preserve more detail in motion, texture, and gradients; fewer bits force the codec to discard information, which shows up as blocking, banding, and mushy fast motion. Getting bitrate right is the difference between a crisp clip and a smeared one.

It also governs practical limits. Platforms cap upload sizes and re-encode anything above their target, so a needlessly huge file wastes your bandwidth without improving the final stream. Knowing the target bitrate before you export saves both upload time and quality.

This matters most when you render AI video. A clip from Playcut's AI video generator comes out at a fixed resolution and frame rate, and you often need to hit a specific size for an ad platform, a client deliverable, or a storage cap. The recommended-bitrate lookup here gives you a defensible export target before you transcode.

Recommended bitrate by resolution, frame rate, and codec

The reference table below lists H.264 starting targets drawn from common platform creator guidance. Higher resolution and higher frame rate both raise the recommended bitrate, because there are more pixels and more frames to encode each second.

Codec choice changes the math. H.264 is the universal baseline. H.265 (HEVC) reaches similar perceived quality at roughly 35% lower bitrate, and AV1 at roughly 45% lower. The codec selector applies that reduction automatically, so the recommended number reflects the format you actually plan to export.

Treat every figure as a target, not a hard rule. Content complexity moves the real number — a static talking-head clip compresses far better than confetti or rain. When in doubt, start at the recommended target and adjust by eye. The numbers are date-stamped so you can re-check them against current platform docs.

What is bitrate?

Bitrate is how much data a video spends per second, measured in megabits per second (Mbps) for video and kilobits per second (kbps) for audio. A 10 Mbps clip commits ten million bits to every second of picture.

That budget is the whole story of quality in a compressed file. Give the encoder more bits and it can keep fine texture, smooth gradients and fast motion intact. Starve it and it throws detail away — which is what blocking, banding and smeared motion actually are.

Two files at the same resolution can look completely different. 1080p at 2 Mbps and 1080p at 12 Mbps have identical pixel dimensions and nothing else in common. Resolution is the frame size; bitrate is how much information fills it.

Bitrate table: 1080p, 1440p and 4K

These are H.264 upload targets by resolution and frame-rate band. The calculator above uses this same table, so the numbers here and the numbers it returns cannot disagree.

Figures are H.264 starting targets as of 2026-05. Complex footage — rain, confetti, a whip pan — wants the upper end of each band; a static talking head sits comfortably at the lower end.

YouTube upload bitrate

Upload above YouTube's target rather than below it. YouTube re-encodes every upload to its own delivery ladder, so the file you send is a master, not the stream viewers receive.

A file sent at or slightly above the recommended rate gives that re-encode clean data to work from. One sent under it bakes in compression artefacts that YouTube then re-compresses — damage no amount of platform processing can undo.

Going far above the target mostly wastes upload time. The gain past roughly 1.5× the recommended figure is invisible after YouTube's transcode, so 4K60 SDR at 53 Mbps is a sensible ceiling for most creators.

Audio bitrate

Audio is a small share of the total but the first thing viewers notice. These are the recommended targets by channel layout, and the calculator adds the matching figure to your file-size math.

• Mono — 128 kbps. Voiceover and single-source dialogue.
• Stereo — 384 kbps. The default for music, ambience and most uploads.
• Surround — 512 kbps. 5.1 mixes, rarely needed for social video.

On a 10-minute 1080p upload, stereo audio at 384 kbps adds well under a tenth of the file size. Cutting audio to save space is almost always the wrong trade.

The cost reality of high-bitrate AI video

Bitrate is free to compute, but the video upstream of it is not. Rendering AI video burns credits, and longer or higher-resolution clips burn more. Planning your bitrate and target length first keeps you from over-rendering footage you will only compress away.

Playcut prices on a clear credit ladder (as of 2026-05): Hobby at $9/mo with 500 credits, Pro at $29/mo with 2,000 credits, Studio at $79/mo with 6,000 credits across four seats, and Agency at $149/seat/mo with 10,000 credits per seat. Credit packs never expire — 600 credits for $9, 2,500 for $35, or 5,000 for $65.

The workflow that wastes the least: pick your delivery resolution, use this calculator to set a bitrate and size target, render the clip once in Playcut, then export at that bitrate. You spend credits on the footage you keep, not on resolution you throw away in compression.

Video bitrate calculator FAQ

How does this video bitrate calculator work?

It solves the bitrate identity in your browser. File size in megabytes equals bitrate in Mbps times duration in seconds divided by 8. Pick which value to solve for, type the other two, and it returns the third instantly with no upload.

What bitrate should I use for 1080p video?

For 1080p H.264 at 30fps or lower, common guidance is around 8 Mbps for SDR and 10 Mbps for HDR. At 48-60fps, push to roughly 12 Mbps SDR. H.265 and AV1 hit similar quality at 35-45% lower bitrate — use the codec selector to see the adjusted target.

How do I calculate video file size from bitrate?

Multiply total bitrate (video plus audio, in Mbps) by duration in seconds, then divide by 8 to convert bits to bytes. Example: 8 Mbps over 60 seconds is 8 × 60 ÷ 8, which equals 60 MB before audio. Enable the audio track to fold its bitrate into the total.

Does a higher bitrate always mean better quality?

Only up to a point. Bitrate sets the data budget per second, so more bits preserve detail and motion. Past the codec and resolution sweet spot, extra bitrate inflates file size with little visible gain. Match bitrate to resolution, frame rate, and codec.

Is this calculator free and private?

Yes. Every calculation is pure JavaScript arithmetic running locally in your browser. Nothing is uploaded, no account is required, and no file ever leaves your device.