Compress Video Online
Make videos small enough to send on WhatsApp, attach to an email or upload to a website without waiting all day. Choose a compression level and optionally a lower resolution; the tool re-encodes the video with H.264 right in your browser and gives you a standard MP4.
No upload means no privacy concerns and no queue. Files up to 300 MB are supported.
How to convert video to compressed MP4
Add a video (MP4, MOV, MKV, WebM or AVI).
Pick Light, Medium or Strong compression, and a resolution if you want to downscale.
Click Compress, wait for encoding to finish and download the MP4.
Why use the Convert Now compress video online
Up to 80% smaller
Modern H.264 encoding at a sensible quality level removes most of the bulk.
Resolution control
Keep original, or downscale to 720p, 480p or 360p.
Universal MP4 output
Plays on every phone, computer and platform.
Private
Encoding happens on your own device.
What makes a video file big
Three things drive video size: resolution, bitrate and length. Phone footage is often recorded at 4K with a very high bitrate because the phone has no time to compress carefully. Re-encoding at a lower bitrate with a proper encoder (H.264 with a quality-based CRF setting) typically cuts size by 60–80% with little visible change. Dropping from 4K or 1080p to 720p reduces it further and is plenty for messaging apps.
Speed expectations
Because compression happens in your browser rather than on a server farm, expect it to take roughly the length of the video on a modern laptop, and two to three times that on a phone. For a big file, choose 720p and Strong compression, or trim the clip first. The engine downloads once (about 30 MB) and is cached for the session.
Read the guide: How to Make a GIF from a Video (Free, No Watermark)
Frequently asked questions
How do I compress a video for WhatsApp?
Choose Medium or Strong compression and 720p resolution. Most clips come out well under WhatsApp's limits.
Will compression reduce quality?
Light and Medium are visually very close to the original. Strong shows mild softening but produces the smallest file.
What is the file size limit?
300 MB per file. Trim or downscale longer videos first.
Why does it take a while?
Video encoding is CPU-intensive and runs on your device. It is usually close to real time on a computer.
Is my video uploaded to a server?
No. It never leaves your browser.
What output format do I get?
MP4 with H.264 video and AAC audio – compatible with everything.
Video Tools — all free
Every tool on Convert Now runs in your browser. No account, no limits, nothing uploaded.
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