Compress Video
Reduce video file size with quality options
Configure
About this tool
Choose one supported file from your device (.mp4, .mov, .avi, .mkv). This workflow does not accept a source URL. Uploaded files are processed by SimplifyConvert's server-side media tools. Temporary working files are scheduled for cleanup after processing, while completed downloads use the site's download-result workflow.
Ready to process
Upload one supported file and start processing.
Balance video size, encoding time, and visible quality
Compress Video uploads one MP4, MOV, AVI, or MKV and creates an MP4 with H.264 video and AAC audio. The Compression Level changes encoding speed and target bitrate; the CRF control adjusts visual quality, where lower values retain more detail and usually create larger files.
Useful delivery scenarios
- •Reduce a clip before attaching it to a message.
- •Prepare a smaller review copy for an upload portal.
- •Transcode a supported source into a broadly playable MP4.
How to use this tool
- 1.Upload one supported video no larger than 500 MB.
- 2.Choose Low, Medium, or High compression and set CRF from 0 to 51.
- 3.Process the file, then compare duration, motion detail, audio, and file size with the source.
What the two controls change
- Low uses a faster preset and higher target video bitrate; High uses a slower preset and lower target bitrate.
- CRF runs from 0 to 51: lower is higher fidelity and larger output; higher is more aggressive and can show artifacts.
- Audio is encoded as AAC at 96 kb/s. Resolution is not exposed as a control on this page.
Example: shrink a 1080p screen recording for review
Try Medium with the default quality first. Static slides may compress well, while small interface text and rapid cursor movement can blur. If text is hard to read, lower CRF; if the file is still too large, raise CRF or try High compression.
Why final size is unpredictable
- Duration, resolution, frame rate, source codec, motion, grain, and existing bitrate all affect the result.
- An already efficient source can shrink little, and a very aggressive setting can damage text or motion detail.
- Processing is limited by a 60-second API duration and can time out for demanding files even below 500 MB.
Tune a failed or poor result
- Output looks blocky: lower CRF or choose a less aggressive compression level.
- Output is too large: raise CRF gradually and compare again.
- Request times out: trim the clip first or use a shorter/lower-resolution source.
Continue the workflow
Return to Video tools, or continue with a complementary tool:
Learn how resolution, bitrate, codec, and audio affect video size
Questions about this specific tool
Which input formats are accepted?
The tool accepts MP4, MOV, AVI, and MKV files and produces MP4 output.
What does a lower CRF mean?
Lower CRF retains more visual detail and normally creates a larger file. Higher CRF is more aggressive and can introduce artifacts.
Can I choose output resolution?
No. This page exposes Compression Level and CRF, not a resolution setting. Use Resize Video for dimension changes.
Why did two videos compress differently?
Sources differ in duration, resolution, motion, grain, codec, and bitrate, so the same settings do not produce the same reduction.