Skip to content
GivenTool

Upscale an image 2x, 3x or 4x

Enlarge an image 2x, 3x or 4x (or to a width) with Lanczos-3 resampling and optional sharpening.

Drop a file here or click to browse

Accepts JPG, JPEG, PNG, WEBP, HEIC, HEIF, GIF, BMP, AVIF. Up to 50.0 MB per file.

Stretching a small image in a basic editor gives blocky pixels or a smeared look. This upscaler uses Lanczos-3, the resampling filter used by professional image software: each new pixel is a weighted blend of the surrounding 6 × 6 source pixels, which keeps edges smooth and fairly crisp without the staircase effect. Big enlargements are done in passes of at most 2x, and an optional unsharp mask restores some edge contrast afterwards.

Be clear about what it cannot do: it does not invent detail the way AI "super-resolution" services do. A blurry face stays blurry, just larger. It is well suited to printing a small photo at a bigger size, enlarging icons, logos and screenshots for slides or documents, and meeting a minimum pixel size that a form or marketplace demands.

Everything runs in a Web Worker in your browser. To keep memory use safe, output is limited to 8000 px on the longest side and 24 megapixels; if your settings go beyond that, the image is enlarged as far as the limit allows and the result card says so.

How to use it

  1. Drop an image or click to browse.
  2. Choose 2x, 3x or 4x, or switch to Target width and type the width you need.
  3. Optionally turn on sharpening. Start with 60% amount and a 1.2 px radius; raise the threshold if noise becomes visible.
  4. Click Upscale and download the result. PNG keeps screenshots and graphics lossless; JPG gives smaller photo files.

Frequently asked questions

Is this an AI upscaler?

No. It uses Lanczos-3 resampling, a mathematical filter. The result is smooth and free of blocky pixels, but no new detail is created. AI upscalers guess plausible detail, which can look sharper but may also change faces or text.

What is the largest image I can make?

8000 px on the longest side and at most 24 megapixels (for example 6000 × 4000). Larger outputs can exhaust browser memory, especially on phones.

Should I turn on sharpening?

For photos and screenshots enlarged 3x or more, light sharpening (amount 40-80%, radius 1-1.5 px) usually looks better. For pixel art or flat logos you may prefer it off. Too much sharpening creates bright halos along edges.

Does it keep transparency?

Yes with PNG or WebP output. Transparent pixels are handled with premultiplied alpha, so edges do not get dark fringes. JPG output places the image on white.

How is this different from the image resizer?

The image resizer uses the browser's built-in smoothing and is designed for exact sizes, presets and shrinking. The upscaler runs a dedicated Lanczos-3 filter in steps, which gives cleaner results for large enlargements.

Related tools