Convert FLV to MP4

FLV after Flash

Flash Video, first Macromedia's and later Adobe's, was how most web video worked in the 2000s: news clips, tutorials, video blogs and e-learning players all ran on it, and long webinars and game streams from that time are often FLV too. It outlived the browser plug-in in live streaming. RTMP, the protocol many streaming services take in, carries FLV, so saved streams and recordings from streaming software are often FLV, and OBS Studio can still record to it.

Since browsers dropped Flash, nothing in them plays FLV. VLC still does. An MP4 plays in every browser, phone and editor, and Octoolo writes it so it starts playing while it downloads, which suits putting old clips back on a website.

What is inside, and what happens to it

Flash added H.264 in 2007, so many later FLVs hold H.264 with AAC or MP3. Those become an MP4 in moments and are listed as Copied as it is, nothing re-encoded. Earlier files are re-encoded, by the graphics card if it has a video encoder. Since each row names the codec before you start, you know which files will be quick.

Old pictures, honest results

Early Flash video was small, often 320 × 240, at low bit rates. Octoolo keeps that size and never enlarges it, so the MP4 looks the way the FLV did. If a clip looks blocky, the blocks were already in the FLV, and no converter can take them out. For a smaller MP4 to send in a chat, Balanced or Small re-encode even the H.264 ones.

FLV writes as it goes and needs no index at the end, which is one reason it was popular for recording: a file cut off by a crash or a full disk usually still converts up to the point where it stopped. When a copy does not work out, Octoolo falls back to a full conversion automatically. If a long video came as several FLV parts, convert them all and join the MP4s afterwards.

From an old FLV to a clip you can post

Once a clip is an MP4, the rest of the Video Editor is open to it. Trim the start and end, put several clips together with merge videos, or turn a landscape clip into a vertical one for Reels and Shorts with the video resizer. For a whole channel's worth of old clips, gather the MP4s in one place with Save in, then work through them in the editor.

Only want the audio of an old interview or live set? The Sound only tab in the converter saves it as MP3, M4A and more. Each of those exports makes a new file, so the converted MP4 and the original FLV both stay as they were.