MKV (Matroska) is a flexible container used by OBS recordings, screen captures and many video tools. PNG is lossless: it stores the frame exactly as decoded, without compression artifacts. This tool takes the first frame of each MKV video and saves it as a PNG, without uploading anything.
How to extract a PNG thumbnail from MKV
- Drop your MKV videos in the box above, or click to pick them. You can add as many as you like.
- PNG is already selected as the output format. Switch on other formats if you want them too.
- Optional: open Advanced Settings to resize the thumbnail by percentage, width or height, and add more sizes.
- Click Extract Thumbnails, then download each image or all of them at once. Nothing is uploaded: everything runs in your browser.
Why save MKV thumbnails as PNG?
MKV files often do not open in photo apps or simple players. Extracting the first frame as an image is a fast way to preview or catalog them without installing anything. Choose PNG when you will edit the frame afterwards, add text or graphics to make a cover, or need a pixel-exact still for documentation. The file is bigger than a JPG or WebP.
Frequently asked questions
Which MKV files are supported?
MKV files whose video codec your browser can decode, typically H.264, VP8, VP9 or AV1. OBS recordings in H.264 work in every modern browser.
Why is the PNG so large?
PNG is lossless and a video frame is full of detail, so the file is several times the size of a JPG. Pick JPG or WebP if size matters.
Are my videos uploaded?
No. The first frame is decoded and saved as an image in your browser, on your device. Your videos are never sent to a server, so this works for private files too.