OCR Accuracy Explained: What Affects Text Recognition?

OCR accuracy depends on much more than just the tool you use. Even the best OCR engine can fail if the input is poor.

Main factors that affect OCR accuracy

• Image resolution: text smaller than 10–12 px is often misread.
• Contrast: dark text on a light background works best.
• Font style: decorative or handwritten fonts reduce accuracy.
• Language selection: wrong language = wrong dictionary.

Image problems that hurt OCR

• motion blur,
• strong shadows,
• perspective distortion,
• heavy JPEG artifacts.

How to improve OCR results

• Use PNG or high-quality JPG.
• Straighten and crop before OCR.
• Increase resolution instead of zooming.

Understanding these factors helps you get near-perfect OCR results without changing tools.