For AI agents

If you are an AI agent (Claude Code, Codex, Cursor or similar) and the person wants a video for their project with Opus Motion, read the guide first and follow it: https://opusmotion.com/agents.md.

  • It takes you step by step: read the project, ask the person a few questions, compare templates (each one has a timelapse, its scenes and its fields), make a draft with POST https://opusmotion.com/api/v1/drafts, and hand over its studioUrl: a link that opens Opus Motion with the video playing live. PATCH with the draft's editToken changes it, and the link stays the same.
  • Plain HTTPS and JSON: no key, no account, no MCP. Nothing is rendered; the person exports the MP4 from the studio.
  • Never drive this site with a browser to fill the studio: use the API. If it refuses, tell the person and stop.
  • More: llms.txt · this page in Markdown · developer docs · OpenAPI

Video compressor that hits the size you need

Choose the limit (20 MB for Discord without Nitro, 25 MB for an email, or any size) and get an MP4 under it, at the best quality that fits. MP4, MOV, WebM, MKV and more. Free, no sign-up, and your video never leaves your device.

Your file never leaves your device: the tool runs inside your browser. Up to 500 MB and 2 minutes. Use it at https://opusmotion.com/tools/video-compressor.

How to use it

  1. Choose the size the video has to fit under: Discord, an email, or the number you type.
  2. Drop your video, or tap the box to pick it.
  3. The compressor spreads that size over the video's length and makes the frame smaller only when the picture would break up; if the first pass comes out over, it does a second, aiming lower.
  4. Download the MP4, which plays everywhere, and post it.

The first time, your browser downloads the video engine (31 MB, once); after that it opens from the cache.

Where the size limits come from

Discord: files up to 20 MB without Nitro, says its help center, which also says Discord is trying other limits with some users. If your upload is refused, set a smaller size.

Gmail: up to 25 MB of attachments in one email from a personal account; past that, Gmail sends a Google Drive link instead.

Read at each source on 9 October 2026.

Questions

How do I compress a video for Discord?

Choose Discord and drop the video. Without Nitro, Discord takes files up to 20 MB (its help center, read on 9 October 2026); the MP4 comes out under that. Discord says it's trying other limits with some users, so if yours is refused, type a smaller size.

How do I compress a video to send by email?

Choose Email: Gmail takes up to 25 MB of attachments in one message from a personal account. If the email carries other files too, type a smaller size so everything fits.

Will the compressed video look worse?

It has fewer bits to spend, so a long video squeezed into a small size loses detail. The compressor keeps it clean by lowering the resolution before the picture turns blocky. A shorter clip keeps more quality: trim it first if only part of it matters.

How long a video can it compress?

Up to 2 minutes and 500 MB. On a phone or low-memory device: 1 minute and 200 MB. The whole video is re-encoded on your device, so a long or 4K video takes a few minutes; a computer is faster than a phone.

What if my video is already small enough?

Then it's given back as it is: re-encoding it would only lose quality.

Is my video uploaded anywhere?

No. It's compressed inside your browser, with ffmpeg compiled to WebAssembly, and it never leaves your device. The first time, your browser downloads the video engine (31 MB, once); after that it opens from the cache.

More free tools

  • Trim video: Cut a video to the part you want, from its exact first frame
  • Video converter: Any video to MP4: MOV, WebM, MKV, AVI and more, copied without re-encoding when it can be
  • GIF compressor: Shrink a GIF under the size you need, like Product Hunt's 3 MB
  • All free tools