Prepare an MP4 for a phone that requires 3GP
Choose 3GP when the receiving phone or legacy application specifically requests that format. It is a compatibility option for older mobile workflows, not a general upgrade over MP4. For a modern phone, browser, or publishing platform, keeping a compatible MP4 is usually the more practical choice.
MP4 and 3GP: general sharing versus older mobile phones
MP4 is the MPEG-4 Part 14 container from the MPEG standards family. It holds video and audio together and is widely used for phone recordings and web delivery. Playback still depends on the codecs inside it: a modern MP4 may exceed what an older handset can decode.
3GP was specified by the 3rd Generation Partnership Project, or 3GPP, for mobile multimedia. It became common on early camera phones where bandwidth, storage and processing power were limited. Its value is compatibility with those devices. Reducing resolution or bitrate to fit them sacrifices detail.
Use this converter when the phone or application specifically requires 3GP. FastConvert uses MPEG-4 video for this output, so an H.263-only phone may still reject it. Check the device requirements before processing a batch. Keep MP4 for destinations that already accept it.
Match the phone, not just the extension
| Check in the device manual | Why it matters |
|---|---|
| Video and audio codecs | A phone requiring a different codec, such as H.263 video, may reject this MPEG-4 output. |
| Dimensions and frame rate | Older devices may accept only a limited range. There is no universal 3GP resolution. |
| Maximum file size | A smaller frame does not guarantee a file fits an MMS or storage limit. |
Prepare a 3GP the receiving phone can play
Check the device requirements
A .3gp extension alone does not guarantee playback. The phone may impose limits on dimensions, frame rate, video codec, audio codec, and file size. Check its documentation before converting a full batch.
Choose a modest resolution
A small legacy screen rarely benefits from a large source resolution. Select dimensions the device supports and preview small text and motion after conversion instead of assuming a smaller file is always readable.
Keep the MP4 original
Encoding for older devices can discard visual and audio detail. Retain the original MP4 so that future deliveries can use a modern format without starting from an already reduced 3GP copy.
How to convert MP4 to 3GP online
FastConvert uses MPEG-4 video for 3GP output. Convert one short sample with conservative dimensions and play it on the actual receiving device. Save the tested settings as a recipe only after both picture and sound work.
The free allowance is 2 files per batch, up to 100 MB each, and 20 conversions per 24 hours. No account or watermark. Files are uploaded for server-side processing, then scheduled for deletion after 24 hours on the Free plan.
Reuse a 3GP setup for the same phone
Save a 3GP recipe for the phone model that accepts the MPEG-4 output, then use it for the next delivery to that model. Keep a separate recipe if another compatible device needs different dimensions.
A free account includes 1 saved conversion recipe. Paid plans add larger batches, more recipes and delivery to Google Drive or Dropbox after you start each batch.