Convert FLV to MP4 Online

How to convert FLV to MP4

1. 1

   Upload FLV files

   Add one or more FLV files to the queue. The uploader keeps batch items separate.

2. 2

   Configure the output

   Set the available quality or format options, or keep the defaults for a first pass.

3. 3

   Run and save the result

   Run the queue and download the MP4 files individually or together as a ZIP.

Flash Video vs MPEG-4 Part 14 video

Why convert FLV to MP4?

• Compatibility is the main reason to convert when another person or service cannot open the source.
• The new format may support a feature the source container does not.
• The result can be reviewed without changing the file that other people still use.
• MP4 is more appropriate for the target application, device, or delivery channel than FLV.

Will quality change?

The conversion standardizes the container and codecs for compatibility. It is a delivery step, not a lossless remux. Check a sample before processing a large batch.

Processing and limits

Processing

Server-side

Engine

FFmpeg

Maximum size

100 MB per file on the server.

Batch support

Yes, multiple files can be queued; completed results can be downloaded as a ZIP.

Quality controls

Options can adjust quality, output dimensions, audio bitrate.

The file is processed on the server because the conversion requires a server-side engine or a utility operation.

• Compatibility depends on the codecs inside the container, not only the .mp4 extension; advanced subtitles and chapter support vary.
• Check metadata, dimensions, and compatibility after the conversion.
• Very large files can hit the 100 MB server limit before conversion starts.

Platform compatibility

MP4 is a broadly supported target, including all current major browsers for common codecs. The source is FLV, which may have narrower support.

When not to convert

• Avoid repeated lossy conversions when quality matters; start from the highest-quality source available.
• If the file contains sensitive data, review the processing model before uploading it to a server.
• Do not convert when the original FLV must remain the only editable or archival copy.

Frequently asked questions

How do I convert FLV to MP4 online?

Upload a FLV file, choose the available MP4 options, run the conversion, and download the result. The tool is free, supports batches, and accepts server uploads up to 100 MB.

What does Convert FLV to MP4 cost?

It is free, requires no account, and adds no watermark. Server uploads are limited to 100 MB per file, and browser-first paths are limited by device memory.

Does FLV to MP4 conversion lose quality?

The conversion standardizes the container and codecs for compatibility. It is a delivery step, not a lossless remux. Check a sample before processing a large batch.

Is my FLV file uploaded?

Yes. This conversion uses a server-side engine, so the file is uploaded over HTTPS, processed in an isolated request, and removed after the result is produced.

Is batch conversion supported?

Queue multiple files, run them together, and download the finished results as a ZIP. Each server file is limited to 100 MB, and large batches may take longer.

What are the limitations?

Open the downloaded MP4 file in the application or database you plan to use, check the structure against the source, and keep the original until the output is approved.