When you resize an image, the software has to invent pixel values that didn't exist. The method it uses is called interpolation.

The three common methods

  • Nearest-neighbor — copies the closest pixel. Fast and blocky; perfect for pixel art and crisp edges.
  • Bilinear — averages the 4 nearest pixels. Smooth but slightly soft.
  • Bicubic — uses 16 surrounding pixels. The best balance of smoothness and sharpness; the default for photos.

Which to use

Use bicubic for photographs and nearest-neighbor only for pixel art or when you must keep hard edges. Remember: no interpolation adds real detail when enlarging — see how to upscale an image and upscaling algorithms compared. To resize, use the resize tool.