Convert FLV to MKV for Multi-Track Archival
Convert your Flash Video files to Matroska Video online for free. FLV cannot be played in modern browsers or devices since Flash Player was discontinued in 2020 — MKV solves that. No registration, no watermarks, instant download.
Drag & drop your file here, or
Max 500 MB · Max 30 min · Max 4K
How to Convert FLV to MKV — 3 Steps
FFmpeg re-encodes your FLV file to H.264, H.265, or VP9 MKV — multi-track archival.
Upload your FLV file
Select your FLV file from old YouTube video downloads. Files up to 500 MB and 30 minutes in duration are accepted.
Confirm and convert
Confirm you own the file and click Convert to MKV. Processing typically completes in under 60 seconds.
Download your MKV file
Download your MKV immediately — ready to store multiple audio tracks (e.g. different languages) in one file.
Why Convert FLV to MKV?
FLV (Flash Video) cannot be played in modern browsers or devices since Flash Player was discontinued in 2020. Converting to MKV gives you multi-track and subtitles.
Frequently Asked Questions
Why convert FLV to MKV?
FLV (Flash Video) cannot be played in modern browsers or devices since Flash Player was discontinued in 2020. Converting to MKV gives you store multiple audio tracks (e.g. different languages) in one file.
Will I lose video quality converting FLV to MKV?
Our converter outputs H.264, H.265, or VP9 video at high-quality settings. When re-encoding is required, we use settings that minimise visible artefacts. The resulting MKV file will be visually very close to the original.
What FLV files can I upload?
You can upload FLV files from old YouTube video downloads, archived Flash websites, and legacy streaming video from 2005–2015. Files must be under 500 MB, under 30 minutes in duration, and not exceed 4K (3840�2160) resolution.
What is the maximum file size for FLV to MKV conversion?
The maximum upload size is 500 MB for video/audio and the maximum video duration is 30 minutes. Resolution is capped at 1920×1080 (1080p).
Is my FLV file kept private?
Yes. Files are processed privately and automatically deleted within 60 minutes. We never store, sell, or analyse your content.
FLV & MKV Format Guides
Understand the formats you're converting between — specs, pros, cons, and use cases.
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