Video Thumbnail Generator Online Free

Free · no upload · no account

Video Thumbnail Generator

Load a video from your device, scrub to the exact frame, add a short caption and download a ready-to-post thumbnail. Everything runs in your browser — your video never leaves your computer.

PNG & JPG 1280×720 · 1080×1080 · 1080×1920 No watermark

Make your thumbnail

Everything below is computed in your browser — no upload, no queue.

Preview canvas
🎬

Drop a video here, or pick one below

Nothing is uploaded — decoding and rendering happen on your device.

1280 × 720 px
Output size appears after the first render
Controls
MP4 / WebM work best. MOV & HEVC are often not decodable in the browser.
Up to 60 characters, wrapped onto two lines.
Text stays inside a 5% safe margin.
The frame is center-cropped to fill the canvas.
JPG keeps YouTube's 2 MB limit comfortable.
Frame hint strip
Five sampled frames — tap one to jump near the moment
0.0s / 0.0s

Tip: seeks land on the nearest decodable frame, so use the preview as the source of truth.

Saved as thumbnail-1280x720.png — nothing is uploaded. On iPhone, the share sheet opens so you can save to Photos.

How it works

Three steps, about thirty seconds, zero files uploaded.

Step 1
Load your video

Pick an MP4, WebM or MOV from your device. The file is read locally with a blob URL — no upload, no queue.

Step 2
Scrub & caption

Tap a frame in the hint strip to get close, then fine-scrub. Type a caption and drop it top, center or bottom.

Step 3
Download the image

The canvas exports straight to PNG or JPG at the exact pixel size you chose — ready to upload to YouTube, TikTok or Instagram.

Which thumbnail size do you need?

The generator centre-crops your frame to fill the canvas, so nothing gets stretched.

16:9 · 1280 × 720

The YouTube standard. Also the safest choice for blog headers and video embeds.

1:1 · 1080 × 1080

Square crops for Instagram and Facebook feed posts, where tall edges get cut off anyway.

9:16 · 1080 × 1920

Full-screen covers for Shorts, Reels, TikTok and Stories. Keep the caption near the centre.

FAQ

Is my video uploaded anywhere?

No. The video is read from your device with a local blob URL and drawn onto a canvas in your browser. Nothing is sent to a server and nothing is stored.

The preview stays blank — what now?

That usually means the browser cannot decode the codec. HEVC (.mov from iPhone or Final Cut) and some AV1 files are not playable in Chrome or Firefox. Re-export as MP4 with H.264 video and try again.

Why is the captured frame slightly different from the slider position?

Browsers decode to the nearest keyframe when they seek, so the exact millisecond can shift. The preview always shows exactly what will be saved — trust the canvas, and use the hint strip to get near the right moment first.

PNG or JPG?

PNG is lossless and best for text-heavy, graphic-looking thumbnails. JPG at quality 0.92 is much smaller and keeps you well under YouTube's 2 MB upload limit. The estimated size is shown under the preview either way.

How big a file can I use?

There is no hard limit — everything is local — but files above 200 MB or 4K footage can take a few seconds to seek. Keep the tab open while it works.

Can I save to Photos on iPhone?

Yes. On iOS the download button opens the share sheet, so you can save the image straight to Photos or send it to an app.

Latest updates