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Image Upscaler Online Free — PrivaTools

TL;DR: Upload an image and upscale 2× or 4× — uses high-quality Lanczos resampling (no AI, but very fast).

Upscale images online for free — enlarge photos by 2x or 4x using high-quality Lanczos resampling. Supports JPG, PNG, and WebP. Perfect for improving resolution of small images, thumbnails, or screenshots.

Like the rest of the 179-tool PrivaTools suite, Image Upscaler is MIT-licensed and self-hostable. The public demo deletes your file as soon as the response leaves the server — verifiable in the open-source codebase on GitHub.

How to Use Image Upscaler

  1. Upload an image — Select a JPG, PNG, or WebP image. The tool shows the current dimensions.
  2. Choose the scale — Select 2x (double) or 4x (quadruple) enlargement. The tool uses Lanczos resampling for sharp, artifact-free results.
  3. Download the upscaled image — Click Upscale. The enlarged image downloads in the same format as the original with the scale factor in the filename.

Frequently Asked Questions

What upscaling methods are available?

The tool uses Lanczos resampling, a high-quality interpolation algorithm that produces sharp, artifact-free results. Choose 2x or 4x enlargement.

What image formats are supported?

JPG, PNG, and WebP images are supported. The output format matches the input — upload a JPG, get a JPG back.

Is there a maximum image size?

The upscaled result cannot exceed 100 megapixels. For a 4x upscale, this means input images up to about 2500x2500 pixels.

Last reviewed 2026-05-01 by the PrivaTools maintainers. Source code on (MIT-licensed, self-hostable).

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