Video Speed Controller - Online Slow Motion & Timelapse

A Video Speed Controller is a tool that lets you change the playback rate of a video in real-time. You can create slow motion effects (as low as 0.1x speed) or timelapse effects (up to 16x speed). This is useful for analyzing sports footage, reviewing tutorials, creating cinematic previews, or simply saving time when watching long videos. Our tool works entirely in your browser — no upload to any server is required.

Upload your video file (or paste a direct video URL), then select a speed below 1x using the preset buttons (0.1x, 0.25x, 0.5x, 0.75x) or drag the precision slider. At 0.25x, for example, a 1-minute clip takes 4 minutes to play — giving you a detailed slow-motion view. You can also use the frame-by-frame buttons ([ and ]) to step through individual frames for precise analysis. The tool does not permanently alter your original video file.

Select a playback speed above 1x — such as 2x, 4x, 8x, or 16x — to preview a timelapse effect. At 8x speed, a 10-minute video plays in just 75 seconds. This is great for quickly scanning long recordings, creating hyperlapse previews, or checking time-lapse camera footage. While this tool provides a real-time preview, to export a permanently sped-up video, you would need a video editor like CapCut, Adobe Premiere Pro, or FFmpeg.

The tool relies on your browser's built-in video decoder. MP4 (H.264 + AAC) is the most universally supported format across all modern browsers. WebM (VP8/VP9) and OGG (Theora) are also well-supported. MOV files may work in Safari and some Chrome versions. AVI and MKV have limited browser support. If your video doesn't play, try converting it to MP4 format first using a free converter like HandBrake.

Yes! The Video Speed Controller is fully responsive and works on iOS and Android devices. You can upload videos from your phone's gallery, use the touch-friendly preset buttons, and adjust the slider. All keyboard shortcuts have on-screen button equivalents for mobile users. Note that very large video files may take time to load on mobile devices due to memory constraints.

The A-B Loop feature lets you mark a specific segment of the video and replay it continuously. Click "Set A" (or press A) at your desired start point, then click "Set B" (or press B) at the end point. Toggle the loop on with the "Loop" button (or press L). The video will automatically jump back to point A every time it reaches point B. This is perfect for studying a technique, practicing a dance move, or analyzing a sports play in detail — especially when combined with slow motion.

This tool provides real-time preview only — it does not re-encode or export videos. To permanently save a slow-motion or timelapse video, you can use screen recording software (like OBS Studio), or dedicated video editing tools such as CapCut (free), Adobe Premiere Pro, DaVinci Resolve (free), or FFmpeg (command-line). These tools can render a new video file at your desired playback speed with proper audio pitch correction if needed.

When you change the playback rate, the browser speeds up or slows down the audio along with the video. At very slow speeds (0.1x–0.5x), audio becomes deep and distorted. At very fast speeds (4x–16x), audio becomes high-pitched and chipmunk-like. This is standard behavior for HTML5 video playback. Professional video editors use pitch-preserving algorithms when exporting speed-changed videos to maintain natural-sounding audio — a feature not available in browsers but common in tools like Adobe Premiere Pro and Final Cut Pro.

Absolutely not. This tool runs 100% in your browser. When you upload a video, it stays on your device — the file is loaded directly into the browser's video player using a local object URL. No data is ever sent to any server. Your privacy is fully protected. You can even disconnect from the internet after loading the page and upload a video to confirm it works offline.