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FAQ

  • Are files uploaded to cloud servers?

    Never. 100% of processing happens locally in your browser using Wasm.

  • How many operations can I run daily?

    Unlimited. Every PXEL tool is free to use as many times as you like.

  • Do I need an account to use PXEL?

    No sign-up, no login. Just open a tool and start — all features are free.

  • Is batch processing supported?

    Yes, batch operations are supported across all core image & PDF tools.

  • Which file formats are supported?

    JPG, PNG, WebP, GIF, AVIF, SVG, BMP, TIFF, and PDF documents.

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Resize Tools
Guides
How Resize Works — Complete Guide
Comprehensive Guide

How Resize Works — Complete Guide

Learn how resizes image tools work, what algorithms they use, and when to use each format.

By PXEL Engineering Team•Updated 2025•100% Free & Client-Side

Why This Matters

Resize to exact pixel dimensions required by a platform or form
Reduce file size by scaling down high-resolution photos
Prepare images for print at specific inch or centimetre dimensions
Lock aspect ratio to avoid distorted results

Step-by-Step Instructions

1

Upload your image

Select a supported image/PDF file from your device.

2

Set new dimensions

Enter width and height in pixels, or choose a percentage or physical unit.

3

Lock aspect ratio

Toggle aspect ratio lock to keep proportions when changing one dimension.

4

Download

Get your resized image in desired format.

Real-World Applications & Use Cases

Social media profiles

Resize photos to exact platform requirements for profile pictures and cover images.

Print preparation

Set dimensions in inches or CM for accurate print layouts.

Thumbnail generation

Create consistent thumbnail sizes for blogs, videos, and product listings.

Email images

Reduce image dimensions to keep email file sizes manageable.

App and UI assets

Generate exact-pixel assets for iOS, Android, and web interfaces.

Batch standardisation

Resize a collection of photos to a uniform size for galleries or presentations.

Pro Tips from Experts

Downscale for sharpness

Reducing size always preserves more sharpness than enlarging. Capture at a higher resolution when possible.

Use percentage for proportional results

Percentage resize keeps exact proportions without needing to calculate the second dimension.

Avoid repeated resizing

Each resize-and-save cycle can degrade quality. Start from the original file each time.

Check DPI for print

For print, 300 DPI is standard. Use the inch/CM mode to set a size that translates correctly.

Try These Tools Now Online

View All Resize Tools

Resize Image

Resize images by pixels, percentage, or physical units.

Bulk Resize Images

Resize multiple images at once with the same settings.

Frequently Asked Questions

Can I enlarge an image without losing quality?

Some quality loss is unavoidable when enlarging. The tool uses high-quality resampling to minimise it.

What is the maximum output size?

Output can be up to 16,000 × 16,000 pixels.

Does resizing reduce file size?

Yes. Smaller pixel dimensions generally mean a smaller file size when saved.

Can I resize to inches or centimetres?

Yes. Select the unit from the dropdown and enter your desired physical dimensions.

Is aspect ratio locked by default?

Yes. You can unlock it to stretch or squash the image independently.