When your voice or game sound doesn't line up with the video, this audio sync delay calculator converts the offset you measured (in frames) into the exact OBS sync offset in milliseconds — and tells you whether to delay the audio or the video.
How to fix audio sync in OBS
- Record or clip a few seconds where you clap once on camera.
- Scrub the clip frame by frame and count the frames between the visual clap and the clap sound.
- Enter that number and your FPS above, and pick whether the audio is early or late.
- In OBS, right-click the source → Advanced Audio Properties → set Sync Offset (ms) to the value shown (for early audio). For late audio, add a Video Delay (Async) filter to the video/capture source instead.
Why the millisecond value matters
OBS sync offset is measured in milliseconds, but you usually see the problem in frames. One frame at 60 FPS is about 16.7 ms; at 30 FPS it's 33.3 ms. So "3 frames off" means very different delays depending on your frame rate — this tool does that conversion for you: ms = frames ÷ FPS × 1000.
Frequently asked questions
How do I calculate audio sync delay?
Delay in milliseconds equals frames divided by FPS, times 1000. For example 3 frames at 60 FPS is 3 ÷ 60 × 1000 = 50 ms. This tool does the math and tells you which source to delay.
My audio is ahead of the video — what do I enter?
Enter a positive Sync Offset (ms) on that audio source in OBS Advanced Audio Properties. A positive offset delays the audio so it lines up with the later video.
My audio is behind the video — how do I fix it?
You can't push audio earlier with sync offset, so delay the video instead: add a "Video Delay (Async)" filter to the video or capture source, set to the millisecond value shown.
How many ms is one frame?
About 41.7 ms at 24 FPS, 33.3 ms at 30 FPS, 16.7 ms at 60 FPS and 8.3 ms at 120 FPS. One frame equals 1000 ÷ FPS milliseconds.
Why is my OBS audio out of sync in the first place?
Common causes are Bluetooth audio latency, capture-card buffering, and monitoring delay. Wired headphones and matching sample rates (48 kHz across devices) help a lot.
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Last updated: July 2026