Resize by exact dimensions or by percentage, with the aspect ratio locked by default. Handy for upload limits, thumbnails and print-ready crops.
Every image is resized with the same settings.
Size
With the ratio locked, fill in one dimension and the other follows. Enlarging past the original size will look soft — pixels that were never captured cannot be invented.
Resizing without wrecking the picture
Resizing down is safe and almost always worth doing: a 4000-pixel-wide photo displayed in a 800-pixel column is carrying five times the data it needs. Resizing up is a different matter — the detail that was never captured cannot be invented, so enlarging past the original size gives you a soft, slightly plastic-looking image. If you need a bigger version, go back to the original file rather than enlarging a small copy.
Keeping the aspect ratio locked matters more than it sounds. Unlocking it lets you force a picture into a shape it was not taken in, and the result is people who look subtly too wide or too tall. When you do need an exact shape, crop to it rather than squashing to it.
Common questions
What size should images on a website be?
As a rule of thumb, no wider than the space they will occupy, multiplied by two for high-density screens. A photo in a 600-pixel-wide column is well served at 1200 pixels. Full-width hero images are usually fine at 1920.
What happens if I enter only a width?
With the ratio locked, the height is worked out for you so the proportions stay exactly as they were. That is almost always what you want.
What does it do if I give both a width and a height?
With the ratio locked it fits the image inside that box without distorting it, so one dimension may come out smaller than you asked. Unlock the ratio if you genuinely want the image stretched to those exact numbers.
Can I resize a batch to the same width?
Yes. Every image you add is resized with the same settings, and you can take the results as one ZIP.
These utilities are the small end of what we do. TechnoSyn builds custom applications, business systems and internal tools for people who depend on them daily. If you have something larger that needs building, tell us what you are trying to do.