Image Resizer — Exact Pixels or Percentage, In-Browser

← Darkroom IsleThe Creative Island · Island 12

Resize to exact pixels or a percentage — ratio kept or broken, your call.

Choose an image

Width (px)

Height (px)

Or scale (%)

.

How to use this tool

1. Choose your image — its current size fills the width/height boxes.
2. Type new pixel dimensions, or a percentage to scale. With Keep ratio on, changing width auto-computes height from the W:H fields proportionally — type width, then height follows your ratio math if you keep ratio on (or paste both).
3. Press Resize & download — grab PNG or JPG.

Example

A 4000×3000 photo → 1200×900 (30%) for email and web: identical framing, one-ninth the pixels, loads instantly on mobile data.

The formula

new pixels = old × scale%; keeping ratio means height = width ÷ (original W ÷ original H)

What the result means

Downscaling is lossy-but-forgiving: a 30% resize looks nearly identical at screen size and saves massive bandwidth. Upscaling is the honest limit of this bench — it makes bigger files, not more detail. For pixel-perfect framing changes, crop instead of resize.

Frequently asked questions

Is my image uploaded anywhere?

No — resizing happens on a canvas in your browser; the download is generated locally.

What's the best size for web images?

1200px wide covers most full-width blog images; 600–800px for content images. Pair with the compressor for the final byte size.

Why does my upscaled image look soft?

Scaling up spreads existing pixels thinner — no algorithm in a browser can invent the detail that was never captured.

PNG or JPG for the download?

JPG for photos (smaller), PNG for screenshots, text and anything needing transparency.

More tools from Darkroom Isle

Image CompressorShrink to any KBImage CropperRatios & passportsImage ConverterJPG, PNG, WebPAspect Ratio CalculatorOn Palette Atoll

Explore the island world

• Darkroom Isle — the island where this tool lives.
• The Main Island — drive the boat, explore the whole world.
• The 90s Kids Island — where most of us started.

Privacy & data: this tool runs entirely in your browser — nothing you type is uploaded, saved or sent anywhere. · Disclaimer: your images are opened and processed by your own browser only — files never leave your device, and originals are never modified. · Privacy Policy · Disclaimer