High contrast between text and background gives the best results. White or light backgrounds work best.

The more letters visible, the more the engine has to work with. A full word or phrase beats a single letter.

Rotated or curved text can confuse the identifier. Crop and straighten the text before uploading if possible.

Remove as much background as possible. The text should fill most of the image area.

Gradients, outlines, drop shadows and textures can reduce accuracy significantly. Plain filled text is ideal.

Text should be at least 100px tall in the image. Very small or low-resolution text is hard to identify reliably.