Image Upscaler (2x / 4x)
Enlarge an image with multi-step high-quality resampling and adjustable sharpening — processed entirely on your device.
Processed on your device — nothing is sent anywhere.
How it works
- Drop an image onto the tool or click to choose one from your device.
- Pick 2×, 3×, 4× or enter a custom target width, then adjust the sharpening slider while comparing the zoomed crops side by side.
- Choose PNG or JPG and download the upscaled image at its full new resolution.
Frequently asked questions
- How does this image upscaler work?
- It enlarges your image in steps of at most 2× using the browser’s highest-quality resampling, which preserves edges far better than a single big jump. After resizing, an unsharp-mask pass compares the result against a slightly blurred copy and boosts local contrast, restoring the crispness that interpolation softens.
- Can it invent new detail like AI upscalers?
- No, and it is honest about that. This tool performs high-quality interpolation plus sharpening — it makes existing pixels larger and crisper but cannot hallucinate textures or faces the way server-side AI models do. In exchange it is instant, free, unlimited and completely private.
- Are my images uploaded to a server?
- No. The entire pipeline — decoding, multi-step resizing, sharpening and encoding — runs in your browser using the canvas API. Your image never leaves your device, so it is safe to use with private photos, client work or documents.
- How large can the upscaled image be?
- The tool caps output at 12,000 pixels on the longest side and warns you above roughly 6,000 pixels, because very large canvases can exhaust browser memory, especially on phones. If a big upscale fails, close other tabs or try a smaller target width.
- Should I download the result as PNG or JPG?
- PNG is lossless and best for screenshots, logos, line art and anything with text, though files are larger. JPG is much smaller and fine for photos; the tool encodes at high quality, and the size estimate updates so you can compare both before downloading.
About this tool
This image upscaler enlarges photos and graphics to 2×, 3×, 4× or any custom width up to 12,000 pixels, directly in your browser. Instead of stretching the image in one pass — which produces the blurry, smeared look most quick resizers give you — it scales in increments of at most 2× with the browser’s high-quality resampling enabled at every step. This multi-step approach keeps edges and fine structure noticeably cleaner, because each interpolation pass only has to bridge a small gap.
After resizing, the tool runs an unsharp mask over the raw pixel data: it subtracts a slightly blurred copy of the image from the original to find edges, then amplifies them by the amount you set with the slider. This recovers the perceived detail that interpolation inevitably softens. To let you judge the result honestly, the tool shows a 100% zoomed crop of the upscaled output next to the same region of the original, magnified without smoothing — drag either crop to inspect faces, text or texture anywhere in the image.
Everything happens on your device. The image is decoded, resized, sharpened and re-encoded with the canvas API in your browser, with no upload, no queue and no account. That makes the tool suitable for private photos and confidential material, and it means a 4× upscale finishes in seconds rather than minutes. It also means being clear about limits: this is careful interpolation plus sharpening, not generative AI — it cannot invent detail that was never captured.
Typical uses include preparing small product photos for print or larger web layouts, enlarging old low-resolution pictures, scaling pixel-dense screenshots for documentation, and meeting minimum-dimension requirements on marketplaces and stock sites. For best results start from the largest original you have, keep sharpening moderate — high values create halos around edges — and download as PNG when the image contains text or hard graphics.