FLV is an Adobe Flash Video container that may carry Sorenson Spark, VP6, H.264, MP3, or AAC streams.
What this converter actually supports
Convertr uses the deployed FFmpeg toolchain for published audio and video routes. A container such as MP4, MOV, MKV, AVI, or WebM can hold different codecs, so the file extension alone does not guarantee that a particular player will accept the contents.
Convert FLV to MP4 for modern playback and browser support.
The public upload limit is 1 GB. Convertr does not reduce dimensions, duration, resolution, or output quality merely to manage worker load.
Quality and format limits
Keep the original dimensions and frame rate unless you intentionally need a smaller result. Remuxing compatible streams avoids re-encoding; changing codecs is lossy, so repeated conversions should be avoided.
Old or damaged FLV timestamps and codecs can require a full transcode rather than a quick remux.
Published FLV inputs
These links come from the active conversion catalog, not from a generic list of possible formats.
Check that the file opens in its original application, is not encrypted or DRM-protected, and really matches its extension. A damaged header, unsupported internal codec, missing linked asset, or mislabeled file can fail even when FLV is generally supported. Try a different published target only when it fits your goal; changing the extension by hand does not convert the file.