QR Code Error Correction Levels (L / M / Q / H)
When should you use L, M, Q or H? A practical guide to choosing between capacity and damage tolerance for QR codes.
The levels roughly correspond to the share of data that can be restored: L about 7%, M about 15%, Q about 25%, H about 30%. The higher the level, the larger the area of the symbol that may be covered or damaged.
For sharing links, L or M is usually enough. If you plan to place a logo in the center, or print on a surface that wears easily, prefer Q or H.
Higher correction consumes more modules, so the same version stores slightly fewer usable characters. For long content, increase the size or shorten the text.