FLV vs WebM: Which Should You Use?

Side-by-side comparison of FLV and WebM video formats — features, pros, cons, and conversion options.

Quick Answer

FLV is best for Legacy Flash-based web video (largely obsolete). WebM is best for Web video embedding and HTML5 playback.

Quick Verdict

FLV Best for Legacy Flash-based web video (largely obsolete)

✓ Small file size
✓ Fast loading
✓ Flash Player legacy support
✗ Flash is deprecated

Convert FLV to WebM →

WebM Best for Web video embedding and HTML5 playback

✓ Royalty-free
✓ Web-optimized
✓ Good compression
✗ Limited hardware support

Convert WebM to FLV →

Specs Comparison

Side-by-side technical comparison of FLV and WebM

Feature	FLV	WebM
Category	Video	Video
Year Introduced	2003	2010
MIME Type	video/x-flv	video/webm
Extensions	.flv	.webm
Container	✓	✓
Codecs	H.264,VP6,Sorenson Spark	VP8,VP9,AV1,Vorbis,Opus
Max Resolution	1080p	8K
Streaming	✓	✓
Subtitle Support	✗	✓

Pros & Cons

FLV

Pros

✓ Small file size
✓ Fast loading
✓ Flash Player legacy support

Cons

✗ Flash is deprecated
✗ Poor mobile support
✗ Limited modern use

WebM

Pros

✓ Royalty-free
✓ Web-optimized
✓ Good compression

Cons

✗ Limited hardware support
✗ Not supported on all mobile devices
✗ Fewer editing tools

When to Use Each

Choose FLV when...

You need files optimized for Legacy Flash-based web video (largely obsolete)
Small file size
Fast loading

Choose WebM when...

You need files optimized for Web video embedding and HTML5 playback
Royalty-free
Web-optimized

How to Convert

Convert between FLV and WebM for free on ChangeThisFile

Convert FLV to WebM Server-side conversion — auto-deleted after processing Convert WebM to FLV Server-side conversion — auto-deleted after processing

Frequently Asked Questions

What's the difference between FLV and WebM?

FLV is best for Legacy Flash-based web video (largely obsolete), while WebM is best for Web video embedding and HTML5 playback. Both are video formats but they differ in compression, compatibility, and intended use cases.

Is FLV or WebM better for video?

It depends on your use case. FLV is better for Legacy Flash-based web video (largely obsolete). WebM is better for Web video embedding and HTML5 playback. Consider your specific requirements when choosing between them.

How do I convert FLV to WebM?

Go to the FLV to WebM converter on ChangeThisFile. Upload your file and the conversion processes on the server, then auto-deletes. It's free with no signup required.

Can I convert WebM to FLV?

Yes. ChangeThisFile supports WebM to FLV conversion. Upload your file for server-side conversion — files are auto-deleted after processing.

Which is smaller, FLV or WebM?

File size varies depending on the content, compression method, and quality settings of each format. In general, lossy formats produce smaller files than lossless ones. Test with your specific files to compare actual sizes.

Does FLV support subtitle support?

No, FLV does not support subtitle support, whereas WebM does. This may be an important factor depending on your use case.

Is FLV or WebM free to use?

Both FLV and WebM are supported file formats that are free to use. You can convert between them for free on ChangeThisFile — server-side conversions are free with no signup required.

Which format is newer, FLV or WebM?

WebM is newer — it was introduced in 2010, while FLV dates back to 2003. Newer formats often offer better compression and features, but older formats tend to have wider compatibility.