# Video compressor https://flaghand.com/video-compressor makes an MP4 or MOV smaller than a size the person picks: 10, 20 or 50 MB, or any number of MB typed. The browser's own decoder and H.264 encoder (WebCodecs) write it again as an MP4 at the bit rate that size allows; the sound (AAC or Opus) is copied as it was, not encoded again, or left out. On Auto the picture is made smaller (1080p, 720p, 540p, 480p or 360p, by its shorter side) when the bit rate is too low to keep it sharp; 1080p, 720p and 480p can be picked. A phone video keeps its turn. When the first pass comes out over the size, it is encoded again, smaller. The result is checked against, as of November 3, 2026: - Discord without Nitro: 20 MB (Nitro Basic 50 MB, Nitro up to 1 GB). - Flaghand's own upload: MP4 or MOV up to 50 MB. - LinkedIn's Videos API: 500 MB. X without Premium: 512 MB. Free, no sign-up. It runs in your browser: nothing you type or add is uploaded or stored, and there is no API. It needs WebCodecs: a current Chrome, Edge, Safari or Firefox. ## How to use it 1. Drop or choose an MP4 or MOV. 2. Pick the size it has to fit under; it is compressed at once. 3. Download the MP4. An agent can preset the choices in the link's hash, which never reaches a server (the video itself can't travel in a link): https://flaghand.com/video-compressor#size=20&res=720&sound=off Fields: size (MB, any number), res=auto|1080|720|480, sound=on|off. ## Size limits. ### Chat Discord without Nitro **20 MB** Nitro Basic takes 50 MB, Nitro up to 1 GB. ### Posting Flaghand **50 MB** An MP4 or MOV, posted to X, LinkedIn, TikTok or YouTube once you approve it. LinkedIn API **500 MB** MP4, 3 seconds to 30 minutes. X without Premium **512 MB** Up to 2 minutes 20 seconds. Checked on November 3, 2026, from [Discord’s file attachments FAQ](https://support.discord.com/hc/en-us/articles/25444343291031-File-Attachments-FAQ) and the [video specs guide](https://flaghand.com/docs/guides/video-specs-tiktok-x-linkedin). ## Questions. ### How do I compress a video? Drop the MP4 or MOV on the page, or choose it, and pick the size it has to fit under. It is compressed at once; then choose Download MP4. ### Is my video uploaded? No. Your browser’s own video decoder and encoder compress it on your device. The video is not sent anywhere or stored, and the page sets no cookies. ### How do I make a video small enough for Discord? Pick 20 MB: Discord takes files up to 20 MB without Nitro. Nitro Basic takes 50 MB. ### Will the video lose quality? Some: a smaller file keeps less detail. On Auto the page also makes the picture smaller when the size is tight, since a sharp 720p video looks better than a blocky 1080p one. A long video under a small size loses the most. ### What happens to the sound? It is copied as it was, not compressed again, and counts toward the size. Choose Remove to leave it out. ### Which videos work? MP4 and MOV, including iPhone videos, in any format your browser can play. The result is an H.264 MP4, which every network and phone plays. To see whether a video posts as it is, check it in the [video checker](https://flaghand.com/video-checker). Every network’s video sizes and lengths are in the [video specs guide](https://flaghand.com/docs/guides/video-specs-tiktok-x-linkedin). ## Flaghand A compressed video goes into a Flaghand draft like any video (`flaghand media upload FILE`, MP4 or MOV up to 50 MB), and its owner approves the post before it goes out. Flaghand is X and LinkedIn posting for AI agents: your agent drafts through Flaghand's API, CLI or MCP server, you approve the exact preview with your passkey, and Flaghand posts exactly that. Sign up at https://app.flaghand.com/start. In a chat app, add the connector at https://app.flaghand.com/mcp: its sign-in page creates the account. An agent with a shell can start the sign-up for its person over HTTP (https://flaghand.com/llms.txt, Quickstart). For agents: https://flaghand.com/llms.txt (this site) and https://app.flaghand.com/llms.txt (the product's agent guide).