Convert 3GP to MP4
Videos from your first phone, playable on your current one — converted privately on your own machine.
Drop your video or audio here
or
MP4, MOV, WebM, MKV, AVI, MP3, WAV and more — any size, no upload
🔒 Files never leave your device — everything runs in your browser.
3GP is the format of flip phones and early smartphones — tiny videos shot on devices with keypads, saved to memory cards, and copied from phone to phone over Bluetooth. Those clips are often genuinely irreplaceable, and modern players are increasingly unwilling to open them. Converting to MP4 keeps the memory and retires the format.
ConvertUno decodes the 3GP-era codecs (H.263, MPEG-4 Part 2, AMR audio) with its own software decoder, entirely on your device. The files are small by nature, so conversion is quick — and because nothing uploads, a folder of personal phone videos stays personal.
How it works
- Drop your file
Any common format, any size. Nothing is uploaded — the tool runs in your browser.
- Convert
Compatible files are repackaged instantly with zero quality loss; others are hardware-transcoded at high quality.
- Download
Your converted file is ready on your device — nothing to wait for, nothing to delete from a server.
Frequently asked questions
Why does my 3GP video have no sound after playing elsewhere?
Old phones recorded audio as AMR, a codec most modern players skip silently. The conversion re-encodes that track to AAC inside the MP4, which restores sound everywhere.
Can the tiny resolution be improved?
No tool can add detail that was never captured — a 176×144 clip stays 176×144. What the conversion fixes is playability: the MP4 opens on any modern device at its original size.
My 3GP files are from 2005 — will they still work?
Almost certainly. The 3GP standard was tightly specified, so even twenty-year-old files decode reliably. The rare failure is a corrupt file (interrupted Bluetooth transfers were common); the tool reports that clearly instead of producing a broken video.
Is my file uploaded to a server?
No. ConvertUno runs entirely in your browser on your own device. Your file never leaves your computer or phone — there is no upload at all.
Is it really free, with no watermark?
Yes. Processing happens on your device, so serving you costs us almost nothing — no watermark, no account, no file-size limit, no daily quota.