How to choose the best bitrate for streaming

What bitrate controls

Video bitrate is the amount of encoded video sent each second. More bitrate can preserve detail during motion, but only until platform limits, encoder quality, and source resolution become the constraint. Excess bitrate can make a stream less reliable without making it look better.

Audio bitrate also consumes upload, as does protocol overhead. Plan using the whole stream, not only the video number shown in OBS.

Start from stable upload, then keep headroom

OBS suggests roughly 75% of total upload as a starting ceiling; Aparat’s guidance is more conservative at 70%. For a broadcast that includes Aparat, using no more than 70% of a repeatable upload result is a sensible first limit.

Example: if repeated wired tests stay near 10 Mbps upload, keep the complete outgoing stream around 7 Mbps or less. A 6 Mbps video plus audio and overhead may fit; a 9 Mbps video is too close to the edge.

• Run several tests, not one peak result.
• Prefer wired Ethernet over Wi-Fi.
• Leave capacity for audio, protocol overhead, and network variation.
• When locally sending multiple outputs, add every output bitrate together.

Use platform values as references, not universal promises

YouTube’s current H.264 guidance lists 4 Mbps for 240p–720p at 30 FPS, 6 Mbps for 720p60, 10 Mbps for 1080p30, and 12 Mbps for 1080p60. Aparat’s support material suggests about 3 Mbps for 720p. These are platform-specific references, so a shared copied stream must fit the stricter destination.

Set Keyframe Interval to 2 seconds

Keyframes are complete reference frames that let players join, recover, and segment a live stream. Both YouTube’s recommendation and Aparat’s guidance support a two-second interval, making 2 seconds a practical cross-platform OBS setting.

In OBS Advanced Output mode, enter 2 in the Keyframe Interval field. Source Copy preserves what OBS produced; it cannot rebuild missing or badly spaced keyframes.

Fix dropped frames before reducing resolution

OBS says dropped frames are generally a network connection problem. Lower bitrate first, use a wired connection, stop other uploads, and test a different ingest route if available. Dynamic bitrate can hide short disruptions, but it does not repair an unstable connection.

If encoding lag rises instead of dropped frames, the computer or encoder settings may be overloaded. That is a different problem from upload bandwidth.

• Dropped frames: network or ingest path
• Encoding lag: encoder/GPU/CPU cannot keep up
• Rendering lag: scene/GPU rendering cannot keep up
• Player buffering only on one platform: inspect that output and its ingest limits

A repeatable bitrate test

• Choose resolution and FPS based on the content, not marketing numbers.
• Set CBR, H.264/AAC, and two-second keyframes.
• Start at a conservative bitrate below the strictest platform limit.
• Test fast motion for 10–15 minutes while watching OBS Stats.
• Increase only in small steps; reduce immediately when dropped frames appear.