Passport MRZ Validator
Verify passport MRZ check digits per ICAO 9303 and decode the embedded fields.
Validate passport MRZ check digits instantly. Free ICAO 9303 MRZ checker for TD3 two-line passports with field breakdown.
Calculator Inputs
About MRZ Check
Verify passport MRZ check digits per ICAO 9303 and decode the embedded fields.
Lines 1–2 of a TD3 passport carry five check digits: document number, birth date, expiry, personal number, and a composite over all four. Each uses 7-3-1 repeating weights mod 10. This validator recomputes all five and decodes name, dates, and document number.
A pass proves transcription fidelity, not document authenticity — forged booklets pass math too. Everything runs in your browser.
Where it is used
Validating OCR output, testing travel-form inputs, learning MRZ structure, and catching typos before check-in.
How to use the MRZ Check
- MRZ Line 1 (44 chars) — enter the value (e.g. P<UTOERIKSSON<<ANNA<MARIA<<<<<<<<<<<<<<<<<<<).
- MRZ Line 2 (44 chars) — enter the value (e.g. L898902C<3UTO6908061F9406236ZE184226B<<<<<14).
- Calculate — press the Calculate button to see the result instantly above.
Formula
ICAO 7-3-1 weighted sums over document, DOB, expiry, personal, and composite fields.
Examples
Example (ICAO specimen)
Frequently Asked Questions
- Why do OCR scans fail check digits?
- Scanners confuse 0/O, 1/I, 5/S, and 8/B. One wrong glyph breaks its field’s digit — retype suspects manually.
- What is the composite check digit?
- A checksum over the other four checked fields concatenated. It catches errors spanning field boundaries.
- Do ID cards use the same format?
- No — TD1/TD2 cards use three shorter lines with different field positions. This tool covers TD3 passports only.