Exact pixels, on demand
“Image must be 800×600.” “Avatar: 400×400.” “Header: 1500×500.” The web is full of pixel-precise demands, and the usual workarounds are all bad: heavyweight editors for a 10-second job, sketchy upload sites for private photos, or just submitting the wrong size and letting some server-side cropper mangle it. This resizer does the job properly in your browser: type the dimensions (or pick a percentage), keep proportions locked or break them deliberately, and download. The original file on your device is never touched.
How to resize an image
- Drop your image — its current dimensions and size appear immediately.
- Enter a new width or height. With Lock aspect ratio on (the default), the other dimension follows automatically.
- Or choose a preset percentage: 75%, 50%, 25% for shrinking, 200% for enlarging.
- Click Resize image; the file downloads with its new dimensions in the name.
The aspect-ratio lock: your anti-distortion insurance
An image's aspect ratio is its shape, and changing width and height by different factors squeezes that shape — faces widen, circles become eggs, logos look melted. The lock guarantees this never happens by accident: set one dimension, the other is computed. Unlock only when a form genuinely demands an exact, differently-proportioned size — and when you do, consider whether our Crop tool is the better instrument: cropping removes area to reach a shape; resizing unlocked distorts everything to reach it.
Shrinking is free; enlarging has a price
Reducing dimensions discards pixels — the result is clean and sharp, often sharper-looking than oversized originals squeezed by a browser. Enlarging cannot invent detail: going 200% spreads each original pixel across four, and the algorithm smooths the gaps, trading detail for size. It's fine for casual use and far better than nothing for print emergencies, but no enlargement looks as good as a bigger original. Rule of thumb: downscale freely, upscale reluctantly.
Sizes worth memorising
- 1920×1080 — full-HD wallpaper, presentations, hero images.
- 1200×630 — social link previews (Open Graph).
- 1080×1080 — square posts on most platforms.
- 400×400 — safe avatar size almost everywhere.
- 50% — the universal “make this email-friendly” preset.
Know your target, type two numbers, done — pixel-perfect without opening Photoshop or trusting a stranger's server with your photos.
Quick reference
| Property | Detail |
|---|---|
| Input | JPG, PNG, WEBP |
| Modes | Exact pixels or percentage presets |
| Aspect lock | On by default — distortion-proof |
| Downscaling | Clean and detail-preserving |
| Upscaling | Supported, with natural softness (no AI invention) |
| Output name | name-WIDTHxHEIGHT.ext |
| Processing | 100% in-browser, no upload |
Frequently asked questions
How do I resize to exactly 800×600 if my photo is a different shape?
You have two honest options: unlock the ratio and accept distortion (rarely right), or crop to 4:3 first with the Crop tool and then resize — which is what professionals do. The lock exists precisely to stop accidental squeezing.
Will resizing reduce my image quality?
Downscaling keeps images crisp — it just discards pixels you no longer need. Upscaling enlarges what exists and looks progressively softer the further you push; 200% is the practical ceiling for decent results.
What does the percentage preset do exactly?
It multiplies both dimensions by the chosen factor — 50% halves width and height (quartering the pixel count), 200% doubles them. The aspect ratio is always preserved in percentage mode.
Does the file format change?
No — JPG stays JPG, PNG stays PNG, WEBP stays WEBP, at high encoding quality. To change format too, run the result through the Image Converter afterwards.