What does Thumbnail Toolkit do?
Tubelexity resizes, crops and compresses images for YouTube thumbnails. Choose a 16:9 or free crop, set exact dimensions and preview the image at desktop, mobile and recommendation-card sizes. The browser creates a JPEG, PNG or WebP file and shows its output size before download.
How to use Thumbnail Toolkit
- 1Choose a JPEG, PNG or WebP image.
- 2Set the crop, dimensions, format, quality and background.
- 3Compare the source and result at common thumbnail display sizes.
- 4Review the size warning and download the exported image.
Supported inputs and outputs
Inputs
JPEG, PNG, WebP
Outputs
JPEG, PNG, WebP
Practical uses
- Resizing artwork to 1280 × 720
- Compressing a thumbnail below an upload limit
- Checking small-card readability
- Preserving transparent channel artwork
Browser and media limitations
- Very large source images can exceed canvas memory.
- JPEG cannot preserve transparency.
- Image quality depends on export quality and resizing.
- Current YouTube limits should be checked before publishing.
How local processing works
Cropping, resizing and export use browser image decoding and Canvas APIs. The image is processed locally and is not uploaded to Tubelexity.
Frequently asked questions
What size should a YouTube thumbnail be?
A 1280 × 720 image with a 16:9 ratio is a common recommendation, but verify YouTube's current upload requirements before publishing.
Can I compress a YouTube thumbnail?
Yes. Choose JPEG or WebP and adjust quality while watching the calculated output file size.
Will transparency be preserved?
PNG and WebP can preserve transparency. JPEG uses the selected background color because it has no alpha channel.
Does the export match the crop preview?
Yes. The preview and export use the same crop coordinates and output dimensions.