Resize JPG, PNG and WebP by the width or height you need. The original ratio is protected by default.
Just the right size
or click to choose from your device
JPG, PNG or WebP · up to 20 MB per fileOne less task on your list. That is what Prontio is for.
Straight from your computer or phone. Your files stay with you.
The options you need, with results that are easy to check.
Save to your device and share whenever you want.
Your images and documents are processed in the browser. No file is sent to our servers.
Straight answers to help you use it with confidence.
Not while keeping proportions is on, which is the default. Turn it off to choose width and height independently.
Yes, but enlarging an image does not create new detail. For the best quality, use the original at a higher resolution.
Choose JPG, PNG or WebP. When you switch formats, image metadata is not kept.
No. Open Prontio in an up-to-date browser and select your files. Up to 20 files per batch, 20 MB per file and 50 MB in total. Images can be up to 24 megapixels and 16,000 pixels on either side.
Keep proportions enabled and enter a width or height in pixels. A 1200 × 800 image becomes 600 × 400 at 50%. The 25%, 50%, 75% and 100% shortcuts use the first image as a reference. In a batch, the chosen width applies to each image while preserving its own proportions.
Disable Keep proportions to set width and height independently; this can stretch the image. Check the preview before downloading. PNG is the initial format and preserves transparency. Enlarging adds pixels but does not create new detail. To reduce file size in KB, use compression.