MP4
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FLV

Convert MP4 to FLV Online

Convert MP4 to FLV online. Start with free daily conversions, no install, no watermarks, and visible job status.

MP4 to FLV Converter

Upload your MP4 file to convert it to FLV format

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How to Convert MP4 to FLV

Follow these simple steps

1

Step 1: Upload Your File

Upload your MP4 file by dragging and dropping or clicking to browse

2

Step 2: Select Output Format

FLV is automatically selected as the output format

3

Step 3: Start Conversion

Click the Convert button to start the conversion

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Step 4: Download Result

Download your converted FLV file when ready

Convert MP4 to FLV - Complete Guide

Converting MP4 to FLV stays in the video file family but changes the traits that decide size, quality, transparency, editability, or device support. MP4 is a video container format widely used for streaming, mobile playback, social media, and general video sharing. FLV is a video format. Flash video. Below is what actually changes in a MP4→FLV conversion, what is preserved, and when FLV is the better choice than keeping MP4.

What changes when you convert MP4 to FLV

  • Both MP4 and FLV are lossy, so the file is re-compressed during conversion. Keep the output quality or bitrate at or above the source to avoid a visible or audible drop.
  • The video is re-encoded into the FLV format. Because re-encoding is not free, start from the highest-quality source you have and keep quality settings high.

About the MP4 format

MP4 (MPEG-4 Part 14) is the most popular video format worldwide. It offers excellent quality with efficient compression, making it ideal for streaming, sharing, and storage. Our MP4 converter supports all common video formats.

  • Full name: MPEG-4 Part 14
  • Developer: ISO
  • Compression: H.264/H.265 (Video), AAC (Audio)
  • Opens with: every device, every browser, every editor

Where MP4 is strong: plays on virtually every device and platform; efficient H.264/H.265 compression; the default for streaming and social media.

Typical MP4 uses: web and mobile video, social media uploads, general sharing.

About the FLV format

FLV (Flash Video) was popular for web video before HTML5. Our converter transforms legacy FLV files to modern, widely-compatible formats.

  • Full name: Flash Video
  • Developer: Adobe
  • Compression: H.263/VP6 (Video), MP3/AAC (Audio)
  • Opens with: VLC, FFmpeg

Where FLV is strong: small files that streamed efficiently in the Flash era; once the standard for online video.

Typical FLV uses: legacy Flash web video, older online video archives.

What FLV keeps

  • FLV adds: small files that streamed efficiently in the Flash era.

Things to watch out for

  • FLV is less universally supported than MP4 — make sure your target player or platform accepts FLV before converting.
  • One FLV limitation to keep in mind: relies on the discontinued Flash Player.

When to convert MP4 to FLV

  • Convert MP4 to FLV for legacy Flash web video.
  • Convert MP4 to FLV for older online video archives.
  • Pick FLV when you need once the standard for online video.

MP4 vs FLV — format comparison

A quick side-by-side of the structural differences between MP4 and FLV, so you can confirm this is the right conversion for your file:

AttributeMP4FLV
TypeVideo fileVideo file
CompressionLossyLossy
Web-friendlyYesNo
Typical file sizeSmallSmall
Best forweb and mobile videolegacy Flash web video

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Need the opposite conversion?

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Other MP4 Conversions

More formats you can convert MP4 to

Convert MP4 to WEBMConvert MP4 to MOVConvert MP4 to AVIConvert MP4 to MKVConvert MP4 to MP3Convert MP4 to WMVConvert MP4 to 3GPConvert MP4 to MPEGConvert MP4 to MPGConvert MP4 to TSConvert MP4 to OGVConvert MP4 to 3G2Convert MP4 to ASFConvert MP4 to M4VConvert MP4 to AACConvert MP4 to WAVConvert MP4 to OGGConvert MP4 to FLACConvert MP4 to M4AConvert MP4 to WMAConvert MP4 to AIFFConvert MP4 to OPUS
View all MP4 conversions →

Convert to FLV

Other formats you can convert to FLV

Convert MOV to FLVConvert WEBM to FLVConvert AVI to FLVConvert MKV to FLVConvert M4V to FLVConvert WMV to FLVConvert 3GP to FLVConvert 3G2 to FLVConvert MPEG to FLVConvert MPG to FLVConvert TS to FLVConvert MTS to FLVConvert M2TS to FLVConvert VOB to FLVConvert OGV to FLVConvert ASF to FLV
View all FLV conversions →

Popular Related Conversions

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MP4 to FLV FAQ

Because both formats are lossy, the file is compressed again. Keep the output quality or bitrate at or above the MP4 source and the difference will be minimal.
Upload your MP4 file, confirm FLV as the output format, and click Convert. Job status is shown while the file is processed, then you can download the FLV result.
Yes. You can start with free daily conversions, with no signup required for your first jobs and no watermarks on the output. Accounts and paid plans are available for higher-volume work.
No. The MP4 to FLV conversion runs in your browser on any device — Windows, Mac, Linux, iOS, or Android — with uploads and downloads over HTTPS.
MP4 (MPEG-4 Part 14) is a video file format. MP4 files can be played with various video players and media applications.
Upload your MP4 video to the converter, select your desired output format, and click Convert. The job status appears while the video is processed.
You can start with free daily conversions. Accounts and paid plans are available for higher-volume work, and downloaded files are not watermarked.
You can convert MP4 to proof-backed video containers such as MP4, WEBM, MOV, AVI, MKV, FLV, WMV, 3GP, OGV, ASF, plus audio outputs like MP3, WAV, AAC, FLAC, M4A, WMA, AIFF, and OPUS.
Yes! Our MP4 converter works on any device including smartphones and tablets.
Choose the output setting that fits your file-size and playback needs. Re-encoding can change quality depending on codec and bitrate.

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