Compress video files to a target size — email, social, or custom. 100% in-browser.
Upload a video and compress it to your target file size
Video compression runs entirely in your browser using ffmpeg.wasm. Your video file is never uploaded to any server.
Video file size is governed by one number: bitrate — the bits stored per second of video. The tool probes your file's real duration, then works backward from the target size: total bitrate = target bytes × 8 ÷ duration. It reserves ~128 kbps for the AAC audio track and feeds the remainder to H.264 (libx264) as the video bitrate, with -maxrate at 2× and -bufsize at 4× so the encoder can burst on complex scenes, plus +faststart so the MP4 plays while still downloading. Lower bitrate shrinks the file but also softens fine detail and can produce blocky artifacts on fast motion — the preset picker just chooses a target size and the math does the rest.
File size ≈ bitrate × duration ÷ 8. The compressor probes the true duration, derives the target bitrate from your chosen size, and lets libx264 squeeze the video down to match.
Tom records a 90-second software demo (MP4, 85 MB) and needs to email it to a client whose mailbox rejects attachments over 25 MB.
Compress video to a target file size for email, social or web. Browser-based, no upload. Free.
The Video Compressor is a free, browser-based tool that reduces video file size by re-encoding with H.264 video and AAC audio codecs at a lower bitrate. You can target a specific file size (useful for email attachments with size limits) or choose from preset quality levels. All processing happens locally in your browser — no upload, no signup.
Drop your video into the tool. Select a preset (Email, Social Media, Web) or set a custom target size in MB. Click compress, and the tool re-encodes your video in real-time. Download the compressed MP4 file when done. Processing time depends on video length and your device's CPU — typically 30-60 seconds for a 1-minute video.
Yes, 100% free with no signup, no watermark, and no file limits. All compression happens in your browser using the WebCodecs API. Your video never leaves your device.
You set a target file size (e.g., 10 MB for email). The tool calculates the optimal bitrate to achieve that size, then re-encodes the video using H.264 video and AAC audio codecs. The output is a standard MP4 file playable everywhere.
Four presets are available: Email (target ~10 MB, high compression), Social Media (target ~50 MB, medium compression), Web (target ~25 MB, balanced), and Custom (you set the exact target size in MB).
Yes, compression reduces quality — that's how file size is reduced. However, the tool uses modern H.264 encoding which maintains good visual quality even at high compression ratios. For best results, start with a high-quality source video.
Yes. Set a target size (e.g., 25MB for email, 8MB for WhatsApp, 50MB for Discord) and the tool calculates the required bitrate automatically. It re-encodes using H.264 with adjustable resolution (downscale to 720p or 480p) and frame rate. A 200MB 1080p clip compresses to 25MB at 720p/30fps with acceptable quality.
Quality loss depends on the compression ratio. Reducing a 1080p video by 50% (e.g., 100MB to 50MB) is nearly imperceptible on mobile screens. An 80% reduction shows visible artifacts in fast-motion scenes. This tool shows a quality estimate before processing and lets you preview a 5-second sample before committing to the full encode.
This tool is also known by these tasks — each link opens the same tool with a focused guide:
What do you call a crab that plays baseball?
No paywalls, no signups, no data sold. Built by a solo developer who believes useful tools should be accessible to everyone.
☕Support me on Ko-fi— keep tools free100% of proceeds go towards hosting & building more free tools.