AnyTool
Your files never leave your device. All processing happens locally in your browser.

How do I change a video's frame rate in my browser without uploading it?

Open AnyTool's Video FPS Converter, drop in a clip, and pick a target frame rate (24, 25, 30, 50, 60 or a custom value). Simple mode drops or duplicates frames for a fast conversion; Smooth mode uses motion-interpolation (minterpolate) to synthesize in-between frames for fluid slow-motion-style results, though it is much slower in the browser. It re-encodes H.264/AAC with a self-hosted ffmpeg engine — no upload, no CDN, no watermark.

  • Presets 24/25/30/50/60 fps + custom
  • Simple mode: drop/duplicate frames (fast)
  • Smooth mode: motion-interpolation (minterpolate, slower)
  • Re-encodes H.264/AAC — self-hosted engine, no CDN, no upload

What is

Frame rate conversion

Frame rate conversion changes how many frames per second (fps) a video plays at. Simple conversion drops or duplicates existing frames; motion-interpolation synthesizes new in-between frames (e.g. ffmpeg's minterpolate) for smoother motion at the cost of much more computation. Client-side conversion re-encodes the video in the browser, so the file is never uploaded.

Video Tools

Related terms

fpsminterpolatemotion interpolationframe blendingffmpeg

How to Change a Video's Frame Rate

Convert a clip to a new fps in your browser.

45 secWeb browser
  1. 1

    Add a video

    Drop in a clip — it stays on your device.

  2. 2

    Pick a frame rate

    Choose a preset (24–60) or custom fps, and Simple or Smooth mode.

  3. 3

    Export

    Re-encode to H.264/AAC and download — nothing is uploaded.

Result: A video at the new frame rate

Frequently Asked Questions

Presets of 24, 25, 30, 50 and 60 fps, or any custom value you type.

Pick a preset for common targets or set a custom fps for special cases.

Simple drops or duplicates frames (fast); Smooth uses motion-interpolation to create new frames for fluid motion (much slower).

Use Simple for a quick change and Smooth when you want the motion to look genuinely fluid at a higher fps.

No — it is re-encoded entirely in your browser with a self-hosted engine.

The clip never leaves your device and there is no size cap, signup or watermark.

Detailed Explanation

Methodology

How the Frame-Rate Converter Works

AnyTool changes a video's frame rate in the browser with a self-hosted ffmpeg engine (no CDN). For a simple change the fps filter resamples timestamps, dropping or duplicating frames to hit the target rate. For smooth slow-motion the minterpolate filter (motion-compensated interpolation, mci) synthesizes brand-new in-between frames — far higher quality but much slower in single-thread wasm, which the UI makes clear. The stream is re-encoded H.264 + AAC with yuv420p pixels and read back as an MP4 blob. Single-threaded is deliberate: the multi-threaded core needs SharedArrayBuffer + cross-origin isolation (COOP/COEP), which would block cross-origin ad iframes.

  • Runs client-side — the video is never uploaded
  • Self-hosted ffmpeg core — no CDN
  • fps filter resamples timestamps (drop/duplicate frames)
  • minterpolate (mci) synthesizes in-between frames — smoother but slower
  • H.264 + AAC, yuv420p re-encode
  • No backend, no watermark, no size cap
Privacy & Security

Privacy vs Upload-based Converters

Most online frame-rate converters upload your file to a server and cap the free tier or add a watermark. AnyTool re-encodes locally with a bundled engine, so the video never leaves your browser, there is no size limit, no watermark and no signup, and it works offline after the first load.

Frame-rate conversion: AnyTool vs typical tools
CapabilityAnyToolTypical tools
Data handlingIn your browserOften uploaded
Engine sourceSelf-hosted (no CDN)CDN / server
Simple changefps filter (drop/dup)Varies
Smooth interpolationminterpolate (mci)Rare
Watermark / capNoneCommon
CostFree, no signupFree/limited

AnyTool is a privacy-first client-side frame-rate converter — re-encoding runs locally and nothing is uploaded.