Video Speed Changer

Adjust video playback speed online, supports 0.1x–10x speed adjustment, create fast-motion and slow-motion effects, high-performance native processing

Bug report

Browser execution mode: Your data is processed in your browser and is not uploaded to the server.

Speed and Stability: Processing speed depends on your device and browser. For large batch work, the desktop version may be more stable.

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If the online tool fails to load or run, try the desktop tool.https://tools.yikeaigc.com/

Tool Usage

Return to old version

A desktop version is available with more powerful, stable features. Open desktop version

Select videos and set speed, audio, and output options before processing. Processing is done on this device. Batch tasks package all successful results into a ZIP.

Select videos to change speed

Supports common videos such as MP4, WebM, MOV, M4V, MKV

Click to select videos, or drag files here The UI shows up to the first 20 files. All selected files will be processed.

Speed and output options

Set options before processing

Keep original playback speed

1.00x Speed multiplier

Exact speed

Range 0.1x - 10x

Output format

Video quality

Audio Processing

Audio bitrate

Frame rate

Add speed suffix to filenameSingle files show the speed; duplicate batch names get numbers. Keep original metadataTries to keep source title, author, and other info. Continue after failureContinue with remaining files if one fails. Use ZIP compressionVideo compression gains are usually limited. Packaging may be slower.

Current settings

Review before processing

Files to process0

Speed multiplier1.00x

Estimated durationPending read

Output formatMP4

Audio ProcessingKeep pitch

File namingAdd suffix

Slow motion increases output duration and size; high speed shortens duration, but re-encoding still takes time. Process large files in batches.

Batch Speed Processing

Processing engine not loaded

Click Start to load the local FFmpeg component. First load may take a while.

Check the files and settings, then click Start.

Preview and download results

Success

Failed

0 B

Result size

Not generated

ZIP status

After processing, the first 9 results appear here. Download files individually or all as a ZIP.

Instructions

Software Usage Instructions

Select video files: Click the “Select Video” area and choose the video files you want to change the speed of. Batch selection is supported. The interface displays the first 20 files, but all files will be processed.
Set the speed multiplier: You can use presets such as 0.25x, 0.5x, 1.5x, 2x, 4x, and 10x, or manually enter a speed between 0.1x and 10x.
Configure output parameters: Select the output format, video quality, audio processing method, audio bitrate, and frame rate. Slow motion increases the duration, while fast motion shortens it.
Set file naming: The original file name is used by default. To distinguish different speeds, you can check “Add speed suffix to file name”. If duplicate names occur, numbers will be appended automatically.
Save common settings: Click “Save Settings” to save the current parameters, which will be applied automatically the next time you open the tool.
Start processing: Go to the “Start Processing” step, confirm the files and parameters, then click “Start Speed Change Processing”.
Preview and download: After processing is complete, you can preview some results. Individual files can be downloaded directly, and multiple files can be saved as a package by clicking “Download All Results ZIP”.

FAQ

A: 0.25x to 0.5x is suitable for slow-motion observation; 1.25x to 2x is suitable for faster viewing; 3x to 10x is suitable for fast-forwarding, time-lapse, and compressing long video content.

A: When you select “Sync speed and preserve pitch”, the audio will change along with the video duration while keeping the original pitch as much as possible. When you select “Change pitch”, the sound pitch will rise or fall with the speed.

A: Yes. Select “Remove audio” in the audio processing options, and the output video will contain no sound. This is suitable for creating silent fast-motion, slow-motion, or material previews.

A: The original file name is used by default. If multiple results have duplicate names, the tool will automatically append numbers to the file names. If the speed suffix is checked, the corresponding speed will be added to the file name.

A: You can choose “Balanced” or “Small Size” quality, process multiple files in batches, and keep the page open. Slow motion, high resolution, and long videos usually require more processing time.

A: Common reasons include corrupted files, non-standard encoding, insufficient device memory, or oversized files. You can try changing the output format, reducing quality, removing audio, or processing in batches.