Online services for enhancing or enlarging images

Sometimes you need to make a photo or illustration larger. Simply enlarging a raster image significantly degrades the original quality. Simply stretching (Inkscape, Photoshop → Image Size → Scale) = loss of quality → may be rejected. When enlarged, spots, noise, and distortion are visible. Manually removing defects is too labor-intensive. Sometimes an image might be suitable for a stock photo, but how can you improve the quality? It's better to use AI upscalers that "draw" pixels.

• Upscayl (free, offline)
• Bigjpg.com (online, free with limitations)
• Let's Enhance (online, free credits available)
• Topaz Gigapixel AI (best, but paid)

Why 5 MP is sometimes "not enough"

• Megapixels ≠ pixels on the longest side
• For example: a 2500×2000 px image = 5 MP. Technically, it's 5 megapixels.
• But Shutterstock and Adobe Stock often require not only 4–5 megapixels, but also at least 2000 pixels on the shorter side.
• If your image is narrow (for example, 4000×1200 pixels), then megapixels are sufficient, but the resolution is not.