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Image Resizer
Pixels or Percentage, Your Call

Scale images to exact pixel dimensions or by percentage. Aspect-ratio locking prevents distortion, batches process in one pass, and nothing uploads.

Percentage Mode
Pixel Precision
Batch Resize
Aspect Protection
100% Online|No Installation|Private & Secure

Resizing options

  • By pixelsWidth / height
  • By percentage5% - 200%
  • Aspect lockBuilt in
  • Output formatsJPG / PNG / WebP

How to resize images

  1. 01Add your imagesOne file or many - the batch queue handles them identically.
  2. 02Choose pixels or percentEnter exact dimensions, or drag the scale slider for proportional sizing.
  3. 03Download resized copiesEvery output reports its new dimensions and file size.

Features

Distortion-proof defaults

Aspect ratio locks automatically; leave one field empty and it computes the other.

High-quality downsampling

Large reductions use stepped halving to avoid aliasing artifacts a single draw would cause.

Upscaling available

Percentages up to 200% work for modest enlargements with smoothing.

Format conversion inline

Resize to WebP while you're at it - no separate conversion step.

Live dimension readout

See computed output size before committing.

Memory-conscious

Sources decode at capped resolution so huge photos don't crash mobile tabs.

Resizing jobs this handles daily

Blog content widthAvatar creationEmail header artDocumentation screenshotsMarketplace photos

Resize once, benefit everywhere

Layout discipline

Images sized to their containers eliminate layout shift and wasted bytes.

Consistent sets

Batch mode makes gallery thumbnails uniform without manual repetition.

Faster everything

Properly sized images load faster, scroll smoother, and sync quicker.

Safe experimentation

Originals stay untouched; resizing creates new files.

Resampling Basics

Why downscaling well is harder than it looks

Shrinking an image means deciding what happens to pixels that disappear. The naive approach samples sparsely - take every fourth pixel for a 4× reduction - which randomly drops thin lines and creates shimmering moiré in patterns. Quality resampling averages neighborhoods instead, blending away detail smoothly.

For extreme reductions, the best technique operates in steps: halve repeatedly with high-quality filtering, then make the final adjustment. Each halving keeps the averaging kernel proportionate to the remaining detail. This is exactly what the engine does internally, which is why 4000→400 pixel conversions come out clean where quick tools produce crunchy edges.

Upscaling is the mirror problem with a fundamental difference: new pixels must be invented. Interpolation guesses them from neighbors, which is why 200% enlargements look soft rather than wrong. Beyond that, genuine detail requires information that isn't there - the honest limit of any resizer.

Notes from people who use this often

“All my blog images go in at 1600px wide now. Editors stopped complaining about slow media libraries.”

Viktor Hansen - Content marketer

“Batch-resizing event photos to web size used to be an evening chore. Now it's ninety seconds.”

Amara Diallo - Community manager

“Screenshot docs finally look uniform - same width, same weight, every page.”

Steve Carr - Technical writer

Frequently asked questions

How do I resize without losing aspect ratio?

Keep aspect lock enabled and enter either width or height - the other dimension calculates automatically.

Can I resize multiple images at once?

Yes. Drop any number of files and they all receive identical treatment in one batch.

What does percentage mode do?

It scales both dimensions proportionally - 50% halves width and height, quartering total pixels.

Will resizing reduce image quality?

Downscaling with proper filtering preserves perceived quality extremely well. Large upscales necessarily soften.

Can I convert format while resizing?

Yes - choose JPG, PNG, or WebP output regardless of the source format.

Is there a maximum image size?

Sources up to 30 MB decode fine; internal processing caps dimensions to protect mobile memory.