LINE Video Compressor

Shrink a video into a LINE-friendly H.264 / AAC MP4 so it shares and plays smoothly in chat.

Local processing only — your file never leaves the browser

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Drag & drop a video, or tap to select

MP4 / MOV / WebM and more, up to 500 MB

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Quality preset

This compresses to a widely compatible H.264 / AAC MP4. LINE may re-compress video on its side, and exact limits depend on the send method (chat vs. file), device, OS, and app version — so this optimizes for smooth sharing rather than guaranteeing a specific size.

Compressing… 0%

Download compressed video

What this tool does

Three presets: Small (720p), Balanced (720p), and High (1080p)
Targets a smaller file via bitrate control while keeping a smooth, compatible MP4
H.264 video + AAC audio with faststart for quick playback
Accepts MP4, MOV, WebM, and more, up to 500 MB
Runs locally with ffmpeg.wasm — your video never leaves your device

How to use

1
Drop a video
Any common format works; the audio and video streams are re-encoded.
2
Pick a preset
Small for the lightest file, Balanced for everyday sharing, High for 1080p quality.
3
Compress and download
Preview the result, then download the MP4 to share on LINE.

What each setting means

Quality preset

Small = 720p with the smallest target, Balanced = 720p mid-size, High = 1080p larger target. The bitrate is derived from the clip length to approach the target.

Common pitfalls

Symptom: The file is still bigger than I hoped

Cause: Target size is approximate; very long or highly detailed clips need more bits.

Fix: Use a smaller preset, or trim the clip first.

Symptom: LINE compressed it again after sending

Cause: LINE may re-encode video on its side depending on how it is sent.

Fix: Send as a file rather than an inline chat video if you want to preserve quality, where supported by your app version.

Symptom: Quality dropped a lot

Cause: A small target on a long clip forces a low bitrate.

Fix: Pick a higher preset or shorten the clip so each second gets more bitrate.

Equivalent FFmpeg commands

Reference commands you can run on the desktop FFmpeg CLI.

Compress to 720p, ~50 MB target (8 Mbit example)

ffmpeg -i in.mp4 -vf scale=-2:720 -c:v libx264 -preset veryfast -pix_fmt yuv420p -b:v 8000k -maxrate 8000k -bufsize 16000k -c:a aac -b:a 128k -movflags +faststart out.mp4

Browser support & limits

Target size is approximate (derived from clip length); it is not a guaranteed cap.
LINE may re-compress video on its side; exact limits depend on the send method, device, OS, and app version.

Privacy

This tool runs ffmpeg.wasm directly in your browser. Files never leave your device — everything runs locally. Read the privacy policy →

Frequently asked questions

What size limit does LINE have?

LINE does not publish a fixed video size or length limit, and behavior varies by send method (chat vs. file), device, OS, and app version. This tool optimizes for smooth sharing rather than targeting an exact published cap.

Will LINE compress my video again?

It can, depending on how you send it. Starting from a clean, compatible H.264/AAC MP4 gives the best chance of a good result.

Which preset should I use?

Balanced (720p) suits most chats. Use Small to keep the file as light as possible, or High (1080p) when quality matters more than size.

Is my video uploaded?

No. Compression runs entirely in your browser via ffmpeg.wasm; nothing is sent to a server.