Upscaling images (making them larger) is inherently challenging because you are creating pixels that did not exist in the original. However, modern techniques can produce surprisingly good results for moderate upscaling.
Browser-based tools like ImgTools use bilinear or bicubic interpolation for upscaling. These algorithms blend existing pixels to create new ones, producing smooth but somewhat soft results. For 1.5x to 2x upscaling, the results are generally acceptable.
For best upscaling results, start with the highest quality source available. Avoid upscaling images that have already been heavily compressed, as compression artifacts will be amplified. Apply subtle sharpening after upscaling to restore edge definition.
With ImgTools, upload your image and set the target dimensions larger than the original. The Canvas API applies high-quality interpolation automatically. For significant upscaling (3x or more), consider AI-powered dedicated upscaling tools.
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