The second number is a Western digit
2026-02-10 · Hindi captchas
The word is Devanagari. The other number is 0–9 as used on the portals this model was measured on.
The layout is a word, an operator, and a digit. इकतीस + 6 is the shape. Both sides as words, or the digit written as ६, is a different captcha and is not what hindi_math claims to read.
If your sample is a row of Devanagari digits only, do not set math and hindi. You will get a confident-looking failure or an unreliable read. Contact the address on the contact page if that is the captcha you have. The README notes this limit on purpose.
When the digit is Western, the path is the supported one. Crop tight so the word and the digit are both in the frame. Cutting off the digit leaves a word with no sum.
length is not how you solve these. The answer length varies. Leave length unset.
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