Bitrate Calculator

How we calculate

Most results here are exact arithmetic. One, the recommended streaming bitrate, is a model. This page shows both, so you can check any number yourself.

Units

  • Bitrates are decimal. 1 kbps = 1,000 bit/s, 1 Mbps = 1,000,000 bit/s. Encoders, ISPs and streaming platforms all use these.
  • File sizes can be decimal or binary. Decimal: 1 MB = 1,000,000 bytes (drive makers, macOS, most websites). Binary: 1 MiB = 1,048,576 bytes (Windows Explorer, which labels it “MB”). Every calculator that shows sizes has a Size units switch, remembered in your browser.
  • 1 byte = 8 bits.

Bitrate, file size and duration

size (bytes) = bitrate (bit/s) × duration (s) ÷ 8, rearranged to find whichever value is missing. This is exact. Real files differ slightly because containers add overhead (typically under 1–2%) and variable-bitrate encodes don’t hit their average precisely.

Target file size

  1. Keep back the safety margin: usable = target × (1 − margin).
  2. Total bitrate = usable × 8 ÷ duration.
  3. Video bitrate = total − audio, rounded down to a whole bit per second so the result never overshoots.

The ffmpeg commands use each encoder’s documented two-pass mode: -pass 1/2 for libx264 and libaom-av1, and -x265-params pass=1/2 for libx265.

Recommended streaming bitrate (a model)

There is no single correct bitrate for a resolution. It depends on the content, encoder, preset and codec. We use a transparent rule of thumb, fitted to widely published streaming guidance:

bitrate = 3,000 kbps × (pixel rate ÷ 1280×720×30)0.73 × codec factor × motion factor

  • Pixel rate is width × height × frames per second. The exponent below 1 reflects that encoders need fewer bits per pixel as resolution and frame rate rise, because neighbouring pixels and frames are more alike.
  • Codec factor: H.264 (AVC) 1, H.265 (HEVC) 0.7, AV1 0.6. Newer codecs reach similar quality with less data; the real saving varies by encoder.
  • Motion factor: low motion 0.7, medium motion 1, high motion 1.35.
  • Range: “acceptable” is 75% of the recommendation and “high quality” is 140%. Results are rounded to 50, 100 or 500 kbps steps.

For H.264 at medium motion this gives about 3,000 kbps at 720p30, 5,400 kbps at 1080p30, 9,000 kbps at 1080p60 and 24,500 kbps at 4K60. Those figures sit inside the ranges commonly published for live streaming. Platforms set their own limits, and some cap standard streams below what 1080p60 ideally needs, so always check your platform’s current ingest guidance.

Resolution H.264 (AVC)H.265 (HEVC)AV1 H.264 range
360p 30 · 640×360 1,100 kbps 750 kbps 650 kbps 800–1,500
360p 60 · 640×360 1,800 kbps 1,300 kbps 1,100 kbps 1,400–2,500
480p 30 · 854×480 1,700 kbps 1,200 kbps 1,000 kbps 1,200–2,300
480p 60 · 854×480 2,800 kbps 1,900 kbps 1,700 kbps 2,100–3,900
720p 30 · 1280×720 3,000 kbps 2,100 kbps 1,800 kbps 2,300–4,200
720p 60 · 1280×720 5,000 kbps 3,500 kbps 3,000 kbps 3,700–7,000
1080p 30 · 1920×1080 5,400 kbps 3,800 kbps 3,300 kbps 4,100–7,600
1080p 60 · 1920×1080 9,000 kbps 6,300 kbps 5,400 kbps 6,700–12,500
1440p 30 · 2560×1440 8,300 kbps 5,800 kbps 5,000 kbps 6,200–11,500
1440p 60 · 2560×1440 13,500 kbps 9,600 kbps 8,200 kbps 10,500–19,000
4K 30 · 3840×2160 15,000 kbps 10,500 kbps 9,000 kbps 11,000–21,000
4K 60 · 3840×2160 24,500 kbps 17,500 kbps 15,000 kbps 18,500–34,500

Platform figures (YouTube, Twitch, Discord)

Where a platform publishes its own numbers, the YouTube, Twitch, Discord and OBS calculators use them instead of our model. They were last reviewed on September 26, 2026. The official help pages block automated access from our build system, so each figure was cross-checked against several independent guides that quote them. Platforms change these numbers, so check the sources:

  • YouTube: one recommended H.264 live bitrate per resolution and frame rate (720p to 4K), and upload ranges for SDR and HDR. HEVC and AV1 live figures are the H.264 figure times our codec factor, which is an estimate.
  • Twitch: its recommended settings table, with a 6,000 kbps maximum for standard streams. Resolutions Twitch doesn’t list use our model, and anything above the maximum is flagged.
  • Discord: upload limits of 10 MB (Free), 50 MB (Server Boost Level 2), 50 MB (Nitro Basic), 100 MB (Server Boost Level 3), 500 MB (Nitro). They’re treated as decimal megabytes, which keeps results safely under the limit.

The OBS calculator takes the lowest of three limits: the platform’s recommendation for your resolution and frame rate, the platform’s maximum, and your upload budget. If the resolution you want can’t get its acceptable bitrate, it picks the setting with the most pixels per second that fits.

Video file size and storage

File size adds video and audio bitrates, then 0.5% for container overhead (MP4 and MKV usually add less). Recording storage multiplies the per-camera bitrate by the number of cameras, and keeps the free space you choose out of the drive’s capacity as sold.

Upload speed

By default a stream should use no more than 75% of your measured upload: upload needed = (video + audio) ÷ 0.75. The upload calculator runs the bitrate model for each standard resolution at 30 and 60 fps. It marks a setting comfortable when the recommended bitrate fits, tight when only the acceptable end fits, and too much otherwise.

Audio

Uncompressed PCM bitrate = sample rate × bit depth × channels. FLAC is shown as 50–70% of PCM, its typical range. Compressed formats use common stereo bitrates.

Input handling

Fields accept thousands separators and k / M suffixes (“6k” = 6,000). Negative values, text and absurdly large numbers are corrected with a visible note. Results are always finite, non-negative numbers, and all the maths is covered by automated tests.