Resize an image online
You enter maximum width and height in pixels. The image fits inside that box while keeping its aspect ratio. There are no remote URLs and no disk paths: only the file you upload.
- No account needed
- Temporary result, expires on its own
- Processed on our servers
The image could not be resized
Sending your file
Processing your file
- Uploading to the server
- Processing your file
- Preparing the download
Your image is ready
Download it now: the link is temporary and expires without you deleting anything.
How it works
- Select the image JPEG, PNG or WEBP. The type is detected from the bytes, not the extension.
- Enter the box Maximum width and height in whole pixels. The image is not stretched.
- Download the result The output format is the same as the input, while retention lasts.
Resize is for bringing a camera photo down to a box usable in a form or in mail. You enter maximum width and height in whole pixels. ToolZen fits the image in that box without stretching it. There is no stretch mode and no percentages.
Before processing we measure the raster (width × height). If it exceeds the megapixel cap or the maximum side, it is rejected. Formats: JPEG, PNG, WEBP, detected by bytes. A PDF or a URL does not get in. Only files uploaded from your device.
One file, 25 MB, maximum processing time. The original is deleted when it finishes; the result expires with guest retention. Output format is the input format: a PNG stays a PNG. We do not promise a specific weight and we do not fill the box with bands on the shorter side.
If the photo already fits in the box, it is not enlarged. If one side hits the maximum and the other overflows, it is reduced proportionally. There is no implicit crop: if you want an exact rectangle by cutting the leftover, use crop image. If you only want fewer megabytes without changing size, compress. If the destination asks for WebP, convert afterwards.
Typical mistakes: asking for 0 pixels, a huge box above the cap, a GIF or a TIFF, or a truncated JPEG. In those cases there is a rejection or a job failure, not an invented thumbnail. Related: crop, compress, convert to WebP and strip metadata.
Frequently asked questions
Is the photo stretched?
No. The image is resized to fit inside the box (contain). There is no “stretch” mode.
Is there a megapixel cap?
Yes. If width × height exceeds the published maximum, the job is rejected before processing. There is also a per-side cap.
Do you accept an image URL?
No. Only the file you upload from your device.
Can it take a while on very large images?
Yes. There is a maximum processing time and a megapixel cap.