# YouTube Thumbnail Resizer > A free online tool that resizes a picture to 1280x720 px (16:9) for a YouTube thumbnail by cropping from the centre, fitting inside the box or adding empty space; it never makes a picture larger. The YouTube Thumbnail Resizer changes your picture to 1280x720 pixels, the size people search for when they make a video thumbnail. It opens with the box already filled in and the fit set to crop the extra. You can change the numbers, the format and the fit before you start. ## Key facts - Input: a PNG, JPG, WebP, AVIF, GIF, BMP or TIFF up to 5 MB in the free tool and 10 MB when signed in, and up to 16 MP (4096 x 4096); one picture at a time. - Settings: the box (1280 x 720 px at the start, any size from 1 to 16384 px), how the picture fits (fill and crop, fit inside, or exact size with empty space) and save as JPEG, PNG, WebP or GIF; a picture smaller than the box is not enlarged. - In our test a generated 3000 x 2000 px JPG of 175 KB became a 1280 x 720 px JPEG of 40 KB with Fill the box; YouTube's own help page, read 2026-10-12, lists 3840 x 2160 px, a minimum width of 640 px, about 16:9 and JPG or PNG for a video thumbnail. - Free without an account: up to 10 conversions per minute and 50 per day per visitor, no watermark. Signed in, each render costs 1 credit (100 free credits every month). - Files are deleted automatically: 10 minutes after conversion without an account, 1 day with a free account. - Developers can run the same job with POST https://api.aiipworld.com/v1/image-jobs?op=image_resize (the image as the request body, settings in the query string) and an API key (see the API docs page). ## How it works 1. Open the picture you want to use. The tool accepts one image at a time. 2. Check the box. It opens at 1280 (width) x 720 (height). Change the numbers if you need a different size. 3. Choose how the picture fits the box. "Fill the box (crop the extra)" is the default. 4. Pick a "Save as" format. JPEG is selected first. PNG, WebP and GIF are also in the list. 5. Click "Resize thumbnail" and check the preview before you download. ## How to use the YouTube Thumbnail Resizer The YouTube Thumbnail Resizer does the work on our server. Open your picture, check the box size and click "Resize thumbnail". The result panel shows the new width, height and file size. The tool opens with "Make smaller: width and height" set to 1280 x 720. You can change either number if your thumbnail needs another size. Each run handles one picture. - Start with a picture that is at least 1280 pixels wide, so it can fill the box. - Use the preview to confirm the framing before you save. ## What 1280x720 means 1280x720 is a 16:9 size. It has 1280 pixels across and 720 pixels down. YouTube's help page (read 2026-10-12) says a video thumbnail should have a resolution of 3840 x 2160 pixels with a minimum width of 640 pixels, be near 16:9, be uploaded as an image format such as JPG or PNG, and be up to 50 MB on desktop. Check that page for the current rules, because they can change. A 1280x720 picture is above the minimum width. It is also the size this page opens with because people search for it. If you need a larger size, change the box, for example to 3840 x 2160, but the tool cannot enlarge a smaller picture. ## Choose how the picture fits the box The fit setting decides what happens when your picture does not match the box. "Fit inside the box (no crop)" keeps the whole picture, but one side can end up shorter than the box. "Fill the box (crop the extra)" scales the picture to cover the box and crops from the centre. Nothing is stretched in either case. In our tests, a 3000 x 2000 px picture with Fill the box gave 1280 x 720 px, cropped from the centre. The same picture with Fit inside gave 1080 x 720 px, which is not 16:9. - Fill the box: no empty space, but edges can be cut. - Fit inside: the whole picture is kept, with a smaller side. ## Pictures smaller than 1280x720 The tool does not enlarge a picture. If your picture is smaller than the box, Fill the box makes the box smaller, keeping its proportions, so the result is the largest crop that fits. In our test, an 800 x 450 px picture with Fill the box stayed 800 x 450 px, and the result panel said it was not resized. To get a full 1280 x 720 px canvas from a smaller picture, use "Exact box size (add empty space)". The picture sits in the middle at its own size, with empty space around it. The empty space is white by default. ## Square and portrait pictures A square picture does not match 16:9. In our test, a 1000 x 1000 px square with Fill the box gave 1000 x 563 px, because the tool does not enlarge the picture to fill the box. With Exact box size, the same square gave a 1280 x 720 px canvas with white bars left and right. A portrait picture behaves the same way. A 1080 x 1920 px picture with Fill the box gave 1080 x 608 px. Results vary with the picture, so check the preview before you save. ## JPEG, PNG or WebP for a thumbnail JPEG is the default output. In our test, a 3000 x 2000 px drawn landscape gave a 1280 x 720 px JPEG at 40 KB with quality 80. The same picture as PNG was 149 KB, and as WebP it was 18 KB. JPEG at quality 95 was 82 KB. PNG is lossless but gave the largest file in our test. WebP was the smallest. Pick the format that fits your upload needs, and check the file size in the result panel. - JPEG: the default, with a quality setting from 1 to 100. - PNG: exact pixels, larger files. - WebP: small files in our test. - GIF: up to 256 colours, so it can look rough on full-colour pictures. ## What to check in the result Look at the preview before you download. The crop is taken from the centre, so text or faces near the edges can be cut. Put the most important part of your picture in the middle before you resize. Small text becomes hard to read after shrinking. View the result at the size a viewer will see on a small screen. If parts are lost, switch to Exact box size to keep everything, with empty bars. ## Limits: file size and pixels Free web tool uploads are limited to 5 MB per image. The free web tool allows 30 images per day per visitor without an account, and each picture can be up to 16 MP (4096 x 4096). Signed-in users can upload up to 10 MB per image. Signed-in use costs 1 credit per image, plus 1 credit for each 5 MB of result after the first 5 MB. Resizing costs the same as converting. Failed and timed-out jobs are refunded. Sizes are shown in KB and MB, as the result panel shows them. ## YouTube Thumbnail Resizer from code The API endpoint is POST https://api.aiipworld.com/v1/image-jobs?op=image_resize. Send the raw image bytes as the body, not JSON or multipart. Set Content-Type to image/png, image/jpeg, image/webp, image/gif, image/avif, image/bmp or image/tiff, and send your key in the Authorization header as Bearer, or in x-api-key. Use width and height for the box, and set fit to inside, cover or contain. The response is 202 with a job_id. Poll GET /v1/jobs/:id until the job succeeds, fails or times out. The download_url is short-lived. The page shows a ready cURL, Node and Python example built from the settings you chose. - Possible errors: 400 invalid_params, 400 or 422 unsupported_image, 413 file_too_large, 402 insufficient_credits, 429 rate limited. - The API takes one request per image. There is no batch endpoint and no webhooks yet. ## Privacy: what happens to your picture Your picture is sent to our server to make the result. The uploaded image is used only for that job and is deleted when the job ends, whether it succeeds or fails. The result is deleted after 10 minutes in the free web tool, and no history is kept. Camera and location tags are not copied into the result. You must have the right to use any picture you upload, as set out in our Acceptable Use Policy. ## Questions ### Can I resize a YouTube thumbnail for free? Yes, the YouTube Thumbnail Resizer is free to use without an account. Anonymous use includes a human check, and you can resize up to 30 images per day. ### What is the YouTube thumbnail size? YouTube's help page (read 2026-10-12) asks for 3840 x 2160 pixels for a video thumbnail, with a minimum width of 640 pixels, near 16:9, as JPG or PNG. This tool opens at 1280x720 pixels, also 16:9, because that is the size people search for. Check YouTube's page for the current rules. ### Will the tool crop my picture? Only if you keep the default fit. "Fill the box (crop the extra)" crops from the centre, while the other choices keep the whole picture. ### How do I keep the whole picture? Choose "Fit inside the box (no crop)" or "Exact box size (add empty space)". The second option gives a full 1280x720 canvas with empty bars. ### Why is my result smaller than 1280x720? Your original picture is probably smaller than the box. The tool never enlarges a picture, so it keeps its size or shrinks the box to fit. ### Can I make a thumbnail bigger? No, the tool only makes pictures smaller. To get a larger size, use a source picture that is already large enough. ### Which format should I use? JPEG is the default and is a good starting point. In our test, the same picture was 40 KB as JPEG, 149 KB as PNG and 18 KB as WebP. ### Will the text stay sharp? Results vary with the picture. Small text can become hard to read after shrinking, so check the result at a small size before you use it. ### Can I use a PNG with a transparent background? Yes, PNG and WebP can keep transparency when Keep transparency is on. JPEG has no transparency, so empty areas are filled with the background colour. ### Can I resize thumbnails in my own code? Yes, the API takes one image per request at POST https://api.aiipworld.com/v1/image-jobs?op=image_resize. The page shows ready cURL, Node and Python examples built from your settings. ## Related - [Resize Image to 1080 x 1920](https://aiipworld.com/tools/resize-image-to-1080x1920/index.md) - [Resize PNG](https://aiipworld.com/tools/resize-png/index.md) - [Discord Banner Size and Image Resizer](https://aiipworld.com/tools/discord-image-resizer/index.md) - [Twitch Emote Resizer](https://aiipworld.com/tools/twitch-emote-resizer/index.md) Page: https://aiipworld.com/tools/youtube-thumbnail-resizer/