QiLing Tools

🐢Change Video Frame Rate Online - 24/30/60 fps & Slow Motion

Upload a video and the tool first shows its source frame rate; then pick a target of 24, 25, 30, 50 or 60 fps, or type any custom value. Three methods are available. Duplicate / drop frames is the fastest and lossless: raising the rate repeats frames and lowering it drops them, which is ideal for meeting a platform’s requirement or matching footage. Frame blending cross-fades neighboring frames by time, making motion smoother at the cost of some ghosting on fast action. Motion interpolation uses FFmpeg’s minterpolate to estimate how each block moves and builds real in-between frames — the closest thing to having shot at a higher frame rate — but it is computationally heavy and slow in the browser, so try a short section at 480p first. Slow-motion mode slows the video down 2×, 4× or 8× and fills in the missing frames with the same three methods, with the output frame rate kept at the source rate or set to 30/60 fps, so the result stays fluid instead of stuttering. When changing the frame rate the audio is kept as is; in slow motion it can be slowed to match without changing pitch, or removed. You can also process just part of the video and choose the output resolution and quality.

Free · No sign-up · Runs in your browserLast updated:

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How to use Video Frame Rate Converter

  1. 1Upload a video and check the detected source frame rate
  2. 2Choose Change frame rate or Slow motion, set the target rate or slow-down factor, and pick a method
  3. 3Adjust resolution, audio and time range if needed, then click Convert and download the MP4

FAQ

Will converting 30 fps to 60 fps make my video smoother?
It depends on the method. Duplicating frames repeats each frame, so it looks the same as before. Frame blending smooths motion with slight ghosting. Motion interpolation computes real in-between images and comes closest to footage shot at 60 fps, although occlusions, very fast motion or busy textures can cause warping artifacts.
Why is motion interpolation so slow?
For every frame it searches block by block for motion and then synthesizes new images, which is far more work than normal transcoding, and FFmpeg runs single-threaded in the browser. At 480p each output second typically takes several to a dozen seconds. Test a 5–10 second section first and reduce the resolution to 480p or 360p.
What happens to the audio in slow motion?
By default it is slowed to match without changing pitch (FFmpeg’s atempo filter). The bigger the slow-down, the more smeared it sounds, so at 4× and beyond removing the audio and adding music later usually works better. In frame-rate mode the length does not change and the audio is kept as is.
Is my video uploaded? Is it free?
Nothing is uploaded — everything runs in your browser with FFmpeg (WebAssembly) and is discarded when you close the page. The tool is free, with no sign-up and no watermark.