PostMicroTools
Calculator
Video bitrate & file size
Pick a codec, resolution, fps and duration to estimate the file size and recommended bitrate. The result is instant and shareable by URL.
About this calculator
A video file size is bitrate × duration. For intra-frame professional codecs (ProRes, DNxHR) the bitrate is essentially constant and scales with resolution and fps; for delivery codecs (H.264, H.265) the figure is indicative because they depend on content and encoder settings.
Where do the bitrates come from?
They are estimated with a bits-per-pixel (bpp) model: bitrate = bpp × width × height × fps. The bpp values are calibrated against published data rates for each codec (e.g. ProRes 422 HQ ≈ 220 Mbps at 1080p29.97).
Is it accurate for H.264 / H.265?
It is a high-quality delivery reference. Real bitrate depends on the encoder, preset, content (motion, grain) and CBR vs VBR. Use it for planning, not as an exact figure.
Sizing masters and deliveries in real projects
The most common question this calculator answers is the gap between a mezzanine master and a delivery encode. A 90-minute documentary mastered in ProRes 422 HQ at 1080p25 runs at roughly 184 Mbps — about 124 GB for the finished film. The same cut exported as H.264 at 20 Mbps for an online screener is about 13.5 GB: a 9× difference that decides whether you hand over a drive or a download link.
It also matters upstream. If a platform asks for a UHD ProRes 422 HQ master (≈ 707 Mbps at 25p), a 45-minute episode needs around 239 GB — so a 1 TB delivery drive holds four episodes, not eight. Knowing that before the online session means you order the right media and quote the right transfer times.
For camera-original formats the calculator includes REDCODE, BRAW, ARRIRAW, X-OCN and ProRes RAW, so you can compare acquisition choices too: an hour of BRAW 5:1 in UHD 25p is a fraction of the same hour in ARRIRAW, and that difference compounds across a 20-day shoot.
Should I master in ProRes or deliver H.264?
They serve different jobs. ProRes (or DNxHR) is the mezzanine you archive and re-encode from; H.264/H.265 is what you upload or stream. A typical pattern is one ProRes 422 HQ master plus per-platform H.264 encodes made from it, each checked against the target numbers in the delivery spec validator.
What bitrate should I use for a YouTube upload?
YouTube re-encodes everything, so give it headroom: around 35–45 Mbps for UHD SDR and 12–20 Mbps for 1080p is a common range. Uploading your ProRes master also works if your connection allows it — quality is decided by their transcode either way.
Does audio change the file size much?
Rarely. Uncompressed stereo PCM at 48 kHz / 24-bit adds about 2.3 Mbps — negligible next to a 220 Mbps ProRes video stream. Only multichannel stem deliveries (5.1/7.1 plus M&E) add enough to plan for.
Audio bitrate reference
Searching for an audio bitrate calculator? Audio is the easy half of the equation: unlike video, its bitrate is fixed by format, not by content. Uncompressed PCM is exactly sample rate × bit depth × channels — stereo 48 kHz / 24-bit is 2.3 Mbps (about 1 GB per hour) — and lossy codecs are set by their encoder target.
| Format | Typical bitrate | Per hour | Common use |
|---|---|---|---|
| PCM 48 kHz / 24-bit stereo | 2,304 kbps | ≈ 1.04 GB | Broadcast masters, stems |
| PCM 48 kHz / 16-bit stereo | 1,536 kbps | ≈ 0.69 GB | Location audio, CD-quality |
| AAC 256 kbps stereo | 256 kbps | ≈ 115 MB | Streaming/web delivery |
| AAC 128 kbps stereo | 128 kbps | ≈ 58 MB | Podcast, proxies |
| MP3 320 kbps stereo | 320 kbps | ≈ 144 MB | Legacy delivery |
| PCM 5.1 (6 ch) 48 kHz / 24-bit | 6,912 kbps | ≈ 3.1 GB | Theatrical/OTT stems |
What audio bitrate should I use for a delivery?
Follow the spec: broadcast and OTT masters almost always require uncompressed PCM (48 kHz, 24-bit) per channel, while web/streaming encodes typically use AAC at 128–320 kbps stereo. When in doubt, check the platform's numbers in the delivery spec validator.