Streaming Bitrate & Bandwidth Calculator
Calculate optimal video bitrates, minimum upload bandwidth safety margins, and hourly internet data usage for OBS Studio, Twitch, YouTube Live, Kick, and Facebook Live.
1. Resolution, Frame Rate & Codec
2. Recommended OBS Settings & Bandwidth
The 1.5x ISP Upload Headroom Rule & CBR Encoding
Livestreaming requires constant, unthrottled real-time transmission:
- Why You Need 1.5x Upload Headroom: Internet Service Provider (ISP) upload speeds fluctuate wildly due to local node congestion. If your stream bitrate is 6 Mbps, an ISP upload plan of exactly 6 Mbps will cause thousands of dropped frames. Always ensure your measured upload speed is at least 1.5x to 2.0x higher than your total stream bitrate.
- Always Use Constant Bitrate (CBR): Variable Bitrate (VBR) causes sudden buffering spikes on viewers' mobile connections when intense in-game explosions occur. Always set OBS rate control to CBR with Keyframe Interval = 2 seconds.
- H.264 vs. AV1 / HEVC: While Twitch is limited to H.264 at 8,000 kbps, YouTube Live supports Enhanced RTMP with AV1 and HEVC (H.265), allowing you to broadcast crisp 1440p60 video at just 8,000 kbps with zero compression pixelation.
Worked examples: every preset at the tool's defaults
The tool starts from a base bitrate for each resolution and frame rate, scales it for the motion and the codec, adds the audio bitrate, and then asks for 1.5 times the total as upload speed. The table uses H.264, medium motion and 160 kbps audio. The data column counts a gigabyte as 1,024 cubed bytes, as the tool does, and the last column tests the video bitrate against the tool's 8,000 kbps Twitch limit.
| Preset | Video bitrate | Total | Upload needed | Data per hour | Twitch 8,000 kbps limit |
|---|---|---|---|---|---|
| 1080p60 | 6,000 kbps | 6.16 Mbps | 9.2 Mbps | 2.58 GB | Within |
| 1080p30 | 4,500 kbps | 4.66 Mbps | 7.0 Mbps | 1.95 GB | Within |
| 1440p60 | 12,000 kbps | 12.16 Mbps | 18.2 Mbps | 5.10 GB | Over |
| 4K60 | 25,000 kbps | 25.16 Mbps | 37.7 Mbps | 10.54 GB | Over |
| 720p60 | 4,000 kbps | 4.16 Mbps | 6.2 Mbps | 1.74 GB | Within |
| 720p30 | 2,500 kbps | 2.66 Mbps | 4.0 Mbps | 1.11 GB | Within |
Motion and codec move the numbers a long way. Fast motion multiplies the video bitrate by 1.25, so 1080p60 goes from 6,000 to 7,500 kbps. Slow motion multiplies it by 0.8. HEVC multiplies it by 0.65, which takes 1080p60 down to 3,900 kbps, and AV1 multiplies it by 0.55. The multipliers are the tool's own estimates, and the platform decides which codecs it accepts.
Four hours of 1080p60 at the defaults moves about 10.3 GB, and the same stream in HEVC moves about 6.8 GB. That matters on a metered or mobile connection. The upload column is what to compare against a measured upload speed, taken during the stream and not read from the bill.
Working Vocabulary
Key livestreaming and video encoding terms:
- CBR (Constant Bitrate). An encoding mode where data output remains fixed at a constant speed regardless of scene complexity to prevent stream buffering.
- Keyframe Interval. The frequency in seconds at which a complete full-frame image (I-frame) is transmitted in a live video stream (standard is 2 seconds).
- Bitrate (kbps). The volume of data processed and transmitted per second of video.
- AV1. An open, royalty-free next-generation video codec that provides up to 50% higher compression efficiency than H.264.