YouTube Thumbnail Resizer

Fill frame enlarges the image until it covers the 16:9 output. Any excess is cropped. Use the horizontal and vertical controls to keep a face, product or important label in view. A control has no visible effect when there is no excess on that axis.

Keep whole image preserves all of your original composition and fills the remaining space with a background color. This is useful for screenshots with important content near the edges. The tool preserves proportions in either mode; it never stretches a face to fit.

Pixel dimensions describe the canvas. File size describes the download. A detailed image may take more bytes than a simple image with the same dimensions. This tool lowers JPEG encoding quality as needed to meet your chosen file target and tells you the resulting size before you download.

The 4K preset provides more pixels for a high-resolution source. HD is useful when your original is smaller or a compressed 4K file loses too much fine detail. Enlarging an image does not recover missing detail; compare the result at full size before publishing.

See the current YouTube thumbnail size guide for official recommendations and device-specific upload limits. The tool defaults to a conservative under-2-MB target for video thumbnails you may upload from a phone.

Open a JPG, PNG or WebP under 25 MB and 50 million pixels. Output is a single JPEG. Transparent pixels become your selected background color. The JPEG is a fresh canvas export; this tool does not copy the source file’s metadata.

There is no watermark or account requirement. The image stays in your browser tab; reloading clears it. This free resizer adjusts an existing file and does not generate a new AI image or upload to YouTube.

After downloading, use the thumbnail preview to check the image and title at small sizes. If compression blurs small letters, start with larger text or simpler detail rather than relying on extra pixels alone.