Convert FLV to MP4

FLV to MP4 converter that runs entirely in your browser. 100% free, no signup, no upload — your files never leave your device. One-click batch conversion.

FLV is a fossil of the Flash era — browsers haven't played it since Flash died in 2020. Converting FLV to MP4 rescues old tutorials, game captures, and web-archive videos, re-encoding them to H.264 so they play on modern devices. Expect generation loss if the source used ancient Sorenson or VP6 codecs.

Conversions

Drop any file here or click to browse

All file types supported

About formats

FLV

FLV (Flash Video) is a container format used to deliver video over the web using Adobe Flash Player. Although Flash has been discontinued, FLV files remain common in older video archives. FLV typically wraps Sorenson Spark or VP6 video and MP3 or AAC audio.

Developer: Adobe (Macromedia)
Initial release: 2002
Compression: Lossy
Color depth: 8-bit
Transparency: No
Animation: Yes

Best for

Recovering legacy Flash video archives
Migrating old web video content
Playing retro web animations
Archiving early-2000s online video
Converting old streaming clips

Pros

+Compact streaming for its era
+Wrapped common codecs like Sorenson Spark and VP6
+Widely used in historical web video
+Simple container structure

Cons

−Flash Player discontinued and unsupported
−Low maximum quality and 8-bit color
−No modern codec or HDR support
−Security risks in legacy Flash runtime

MP4

MP4 (MPEG-4 Part 14) is a digital multimedia container format standardized by the Moving Picture Experts Group (MPEG). It stores video, audio, subtitles, and still images in a single file and is the most widely used format for streaming and sharing video across the web, mobile devices, and living-room hardware. MP4 offers an excellent balance between compression efficiency and quality, typically using the H.264 or H.265 (HEVC) video codec together with AAC audio. Its near-universal support makes it the default choice for social media platforms, browsers, phones, and modern TVs.

Developer: ISO/IEC (MPEG)
Initial release: 2001
Compression: Lossy
Color depth: up to 12-bit HDR
Transparency: No
Animation: Yes

Best for

Sharing videos on social media
Streaming video over the web
Playback on phones and tablets
Storing H.264 or HEVC video
Distributing downloadable video clips

Pros

+Near-universal support across devices and browsers
+Excellent compression-to-quality ratio
+Supports subtitles, chapters, and metadata
+Hardware-accelerated decoding on most devices

Cons

−Patent-encumbered H.264/HEVC codecs
−Not ideal for lossless archival
−Editing streams can require re-muxing

How to convert FLV to MP4

1
Select FLV files from your computer, Google Drive, Dropbox, a URL, or by dragging them onto the page.
2
Choose mp4 — or any other format you need as a result (more than 200 formats supported).
3
Let the file convert, then download your mp4 file right away.

FLV vs MP4

Property	FLV	MP4
Compression	Lossy	Lossy
Color depth	8-bit	up to 12-bit HDR
Multi-track	Yes	Yes
DRM support	No	Yes
Open format	No	No

When to use FLV vs MP4

FLV

Recovering legacy Flash video archives
Migrating old web video content
Playing retro web animations
Archiving early-2000s online video
Converting old streaming clips

MP4

Sharing videos on social media
Streaming video over the web
Playback on phones and tablets
Storing H.264 or HEVC video
Distributing downloadable video clips

Use cases for FLV → MP4

Recovering legacy Flash video archives
Migrating old web video content
Playing retro web animations
Archiving early-2000s online video
Converting old streaming clips
Sharing videos on social media
Streaming video over the web
Playback on phones and tablets
Storing H.264 or HEVC video
Distributing downloadable video clips

Frequently Asked Questions

Is converting FLV to MP4 free?

Yes. This FLV → MP4 converter runs entirely in your browser and is completely free — no account, no credits, no watermark.

Which devices and platforms can I use to convert FLV to MP4?

Any modern device with a current web browser: Windows, macOS, Linux, Android, iPhone and iPad. There is nothing to install — the conversion happens locally.

Are my FLV files uploaded to a server?

No. Files never leave your device. The entire FLV → MP4 conversion runs locally in your browser, so your data stays private.

Can I convert multiple FLV files at once?

Yes — batch conversion is supported. Add as many FLV files as you like and convert them to MP4 in one pass, then download the results together.

What is the maximum file size?

There is no fixed server-side limit because the conversion happens in your browser. Practical limits depend on the available memory and CPU of your device.

Will converting FLV to MP4 reduce the quality?

Because both formats use lossy compression, the MP4 output will not bring back any quality that has already been lost in your FLV file. Avoid repeated re-encoding to keep the best quality.

Does MP4 support transparency?

No — MP4 has no alpha channel. Transparent areas of your FLV file will be filled with a solid background colour in the converted file.

How will the file size change after converting FLV to MP4?

Both formats use comparable compression, so the MP4 output will be similar in size to your FLV file — typically within 10–20% of each other.

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FREE

100% Free

No hidden fees, no subscriptions, and no limits. Enjoy complete access to all features gratis.

SIGNUP

No Signup Required

Start converting immediately without creating an account or sharing email address.

PRIVACY

Private & Secure

Your files never leave your device. All processing is completed locally for maximum privacy.

BATCH

Batch Conversion

Convert multiple files simultaneously to save time. Fast and efficient multi-file queue.

LOCAL

Runs in Browser

Utilizes advanced client-side WebAssembly technology to process files directly inside your tab.

FORMATS

200+ Formats

Supports a wide variety of formats including images, documents, audio, video, and more.

USER REVIEWS

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