OBS Offset Calculator

OBS Offset Calculator

Created by Phil Pendlebury

V1.0

Last updated: Sep 03, 2025

A tool to help align / sync your video and audio sources in OBS

Instructions for use:

• In OBS, set all your input sources to have no offsets (so they are all at the default value of 0)
• Add all sources, (audio and video) to a scene
• Record a clapper board or some other tool that will give you a good reference point to sync to.
  • If you have multitrack video available, make sure all cameras / screen captures, and audio sources are visible in the scene on separate tracks
  • Or you can do it one source at a time, using the Master Source in every scene, along with the target source
• Load your recording into a video editor
• Choose your most stable source, this can be audio or video, this will be your Master Source
  • In this application that source should be marked as Master, using the check box and it's Offset (ms) time will always be 0
• One at a time, go through each source and measure the difference (offset) in sync compared to the master source,
  • For example, if the audio of the source you are measuring is 45 milliseconds later than the master source, you will enter 45 into the Offset (ms) columns for that source
  • if the audio is earlier then you will enter a -ve number (example -45)
  • Repeat this for all sources
  • Note: it is not possible to negatively delay audio in OBS, so the calculations are done accordingly by this application by adding an offset to the other items
• The application will calculate the values needed to enter into OBS
• For audio sources, use the Advanced Audio Properties in OBS to enter the values displayed in the OBS (ms) column
• For video sources, add a Render Delay Filter to your source in OBS and enter the value displayed in the OBS (ms) column

Your sources should now be in sync, test this by making a new recording

You can also Export a list the Offsets using the Export Offsets button

You can add new sources by adding them in the app and then clicking Save Sources

You can open the INI file and view it manually

You can also trigger a manual recalculation if required, using Recalculate

The Latency Model section at the top is just for refence and has no bearing on the calculations

The Base Delay figure shows the amount that the Master Source must be delayed by, for reference