What is CRF?
CRF (Constant Rate Factor) controls quality vs. size. Lower = better quality, larger file. 23 is default FFmpeg quality, 28 gives ~40% smaller files with minimal visual difference.
Video tool
Compress Video Online
Reduce video file size online for free. Upload an MP4, MOV, MKV, or AVI file and FormatNest compresses it using FFmpeg's H.264 encoder — smaller file, same visual quality. No software to install.
Complete guide
How to compress a video online
Video Compressor uses FFmpeg's H.264 encoder with a configurable CRF (Constant Rate Factor) setting to reduce video file size. Upload your video, choose a quality preset, and click Compress. Processing happens on a secure server — you'll get a download link when it's ready.
Use CRF 23 for near-lossless quality, CRF 28 for a good balance of size and quality (recommended), or CRF 32 for maximum compression when file size matters more than quality.
Typical results
A 100 MB video typically reduces to 30–60 MB at CRF 28 while remaining indistinguishable from the original on most screens.
Output format
Output is always MP4 (H.264 + AAC) — the most widely compatible video format for web, mobile, social media, and email.
Answers
Video Compressor FAQs
What is Video Compressor?
Video Compressor is a free FormatNest tool that reduces video file size using FFmpeg's H.264 encoder, making videos smaller for sharing, uploading, or storing without noticeable quality loss.
How much will my video shrink?
Typically 40–70% size reduction depending on the original bitrate. A 100 MB video can often be reduced to 30–60 MB at the same visual quality.
What video formats are supported?
MP4, MOV, MKV, AVI, and WEBM are all supported as input. Output is always MP4 (H.264) for maximum compatibility.
What does CRF mean?
CRF (Constant Rate Factor) controls quality vs file size. Lower CRF = higher quality, larger file. Higher CRF = smaller file, lower quality. 23 is default, 28 is a good compression preset.
Is the original file deleted after compression?
Yes. Both the uploaded file and the compressed output are automatically deleted from the server within 30 minutes of the job completing.