How are the frames captured?

The video is loaded into a hidden HTML5 video element. For each timestamp the tool sets currentTime, waits for the seeked event, then draws the current frame onto a Canvas and exports it as a PNG data URL.

What video formats are supported?

Any format your browser can play natively — usually MP4 (H.264), WebM, and often MOV. If the browser cannot decode the codec, the frames cannot be captured.

Is my video uploaded?

No. The file is loaded via a local object URL and processed in the browser. Nothing is sent to a server, so it works offline and your video stays private.

At what resolution are the thumbnails saved?

Frames are captured at the video's native resolution (videoWidth × videoHeight) and saved as full-quality PNGs; the on-page previews are just scaled down for display.

Is there a limit on how many frames I can extract?

For performance the tool caps extraction at 200 frames per run. For very long videos, increase the interval or extract specific sections at a time.

Video Thumbnail Extractor

Pull still frames out of a video in the browser

A thumbnail extractor captures one or more still images from a video at the moments you choose — handy for poster frames, contact sheets, documentation screenshots, or scrubbing through footage frame by frame. This tool does it locally with the HTML5 video element and Canvas, so nothing is uploaded.

How it works

The selected file is wrapped in a local object URL and loaded into an off-screen <video> element. Once metadata is available the tool reads the duration and native resolution. For each requested time it sets video.currentTime and waits for the seeked event to fire — that guarantees the frame at that timestamp is actually decoded and displayed. It then calls ctx.drawImage(video, …) on a Canvas sized to the video and exports the result with canvas.toDataURL("image/png").

In interval mode the timestamps are generated as 0, N, 2N, … up to the duration; in list mode they come from the comma- or newline-separated values you enter.

Tips and notes

Use list mode to grab exact moments (for example a title card at 3.5 s); use interval mode to build an even contact sheet.
Frames are saved at native resolution, so they are suitable for documentation or social poster images.
Some browsers cannot decode certain codecs (HEVC, for instance). If extraction fails, re-encode the source to H.264 MP4 or WebM.
Because seeking is sequential, extracting many frames from a long video takes a little time; keep intervals reasonable.