Ampliador de Imagens com IA — Ferramenta online grátis

Free image upscaler — enlarge images 2x, 3x, or 4x in your browser

Ferramentaolis Image Upscaler enlarges images up to 4x their original resolution entirely in your browser. Using Canvas-based interpolation with optional unsharp mask sharpening, it produces clean, smooth enlargements without uploading your files to any server.

How image upscaling works

When you enlarge an image, new pixels must be created between existing ones. The simplest approach (nearest-neighbor) duplicates pixels, creating a blocky look. This tool uses the browser's built-in high-quality interpolation which applies bicubic-like smoothing to create natural gradients between pixels. The optional sharpening pass then applies a convolution kernel that increases local contrast at edges, counteracting the softness introduced by interpolation.

When to upscale images

• Social media — enlarge small photos for Instagram, Facebook, or LinkedIn where minimum resolution requirements apply.
• Printing — increase resolution for print-quality output (aim for 300 DPI at your target print size).
• Presentations — prevent pixelation when stretching images on large screens or projectors.
• E-commerce — enlarge product photos for zoom features on Shopify, Amazon, or eBay listings.
• Thumbnails to full-size — recover usable resolution from small preview images.

Interpolation methods explained

Bilinear interpolation calculates new pixel values by linearly blending the four nearest original pixels. It is fast and produces reasonably smooth results, but edges may appear slightly soft. Bicubic interpolation considers the 16 nearest pixels using cubic polynomials, producing smoother gradients and better-preserved edges. In this tool, the browser's imageSmoothingQuality setting controls which algorithm is used.

Understanding the sharpen feature

The sharpening pass applies a 3x3 unsharp mask convolution kernel. This technique works by subtracting a blurred version of the image from the original, then adding back the difference scaled by a factor. The result is increased contrast at edges, making text, outlines, and fine details appear crisper. However, excessive sharpening can introduce visible halos (bright or dark rings around edges) and amplify noise in smooth areas like skies or skin.

Choosing the right output format

PNG preserves every pixel exactly with no quality loss, making it ideal for graphics, screenshots, text-heavy images, and anything requiring transparency. File sizes are larger. JPEG applies lossy compression that discards imperceptible detail, resulting in much smaller files. For photographs, JPEG at 90-95% quality is visually identical to PNG at a fraction of the file size. Use the quality slider to find your preferred balance.

Browser-based vs. AI upscaling

This tool uses mathematical interpolation, which smooths and enlarges existing pixels without inventing new detail. AI upscalers like Topaz Gigapixel, Real-ESRGAN, or Waifu2x use trained neural networks that can hallucinate realistic texture, hair strands, fabric patterns, and other fine details that do not exist in the original image. If you need photorealistic enlargement of very low-resolution images, AI tools will produce superior results. For general-purpose upscaling of moderate-resolution images, browser-based interpolation with sharpening is fast, free, and private.