Crop any image to a YouTube thumbnail.
YouTube wants thumbnails at 1280×720 pixels — 16:9 aspect ratio, minimum 640 wide, under 2 MB. Drop an image, get the exact size. Nothing uploaded.
The exact size YouTube wants
YouTube's spec for custom thumbnails is narrow:
- 1280×720 pixels — 16:9 aspect ratio, the same shape as the player.
- Minimum width 640 pixels. Smaller uploads get rejected.
- Under 2 MB. Anything bigger fails to attach.
- JPG, PNG, GIF, or BMP. WebP and AVIF are not accepted.
Source: YouTube Help — Custom thumbnails.
The 1280-wide cap means there's no benefit to uploading a 4K still — YouTube downscales server-side using its default resampler. Pre-cropping at exactly 1280×720 keeps you in control of the resampling quality and stays under the 2 MB limit comfortably for most photos.
Common mistakes
Wrong aspect, ugly letterbox. Uploading a 1080×1080 square (Instagram cover screenshot, designer mockup) gets center-cropped to 16:9 — top and bottom of your subject vanish. The thumbnail you actually wanted is gone before it ever rendered.
Subject too small. Thumbnails render at ~120 wide in the suggested-videos rail and ~246 wide on mobile. If a face is below 25% of the thumbnail height, it disappears at thumbnail size. Fill the frame.
Tiny text. At 120 wide, anything under 60-70 pixels of headline height is illegible. If your text is "readable on desktop preview," it's probably already too small for the rail.
Upload over 2 MB. Photo-quality 1280×720 JPG comes in around 200-400 KB. If you're hitting 2 MB, you're saving uncompressed PNG of a photograph — switch to JPG.
Best practices for thumbnails that get clicked
Face zoom. Single subject, eyes near the rule-of-thirds line, framed shoulder-up or chest-up. Face fills 30-45% of the frame.
High contrast. Light subject on dark background, or vice versa. Avoid mid-tone backgrounds — they wash out in the rail.
Title overlap, not duplication. Your video title sits next to the thumbnail in most surfaces. The thumbnail text should add — an emotion, a number, a counterpoint — not repeat the title.
Test at 120 wide. Resize the thumbnail to 120 pixels wide on your desk and ask if you can still tell what it is. If not, simplify.
Walkthrough: cropping a 4032×3024 phone photo
- Drop the photo in. It loads locally — no server round-trip.
- Pick the YouTube preset (1280×720, 16:9). The crop box auto-centers on the detected face.
- Drag to fine-tune. Pull the box up if you want headroom; pull down to zoom into the subject.
- Pick JPG, quality 85-90. Comes out around 250 KB for a typical photo.
- Download. Drag the file straight into YouTube's thumbnail upload.
Total time: under 30 seconds for a single thumbnail. The file never leaves your device.
Frequently asked
What size is a YouTube thumbnail?
YouTube recommends 1280×720 pixels in a 16:9 aspect ratio, minimum 640 pixels wide. The file must be under 2 MB and in JPG, PNG, GIF, or BMP format.
Does YouTube re-crop my thumbnail?
YouTube may letterbox or crop if your image is not 16:9. Submitting at 1280×720 exactly avoids any surprises and keeps the resampling under your control.
Why does YouTube reject my thumbnail?
Three usual reasons: file is over 2 MB, format is WebP or AVIF (neither supported), or width is below 640 pixels. Saving as JPG at 1280×720 with quality 85 lands inside all three limits.
Can I use a screenshot from my video as the thumbnail?
Yes — drop the screenshot in, pick the 1280×720 preset, and the crop will auto-center on the most visually salient region. Drag to reframe if the auto-pick missed the moment you wanted.