Smog VIN format check

Client

Smog and emissions stations retype VINs into state BAR systems. Format check catches mod-11 failures before the test bay—passing emissions still requires the physical inspection separately.

Before the emissions bay

Copy from door jamb or registration, paste here, confirm mod-11 pass, then enter the same string into the station system—avoids retest fees from single-digit typos.

Privacy: parsing runs only in your browser. This page does not query DMV, insurance, or manufacturer databases—only the published mod-11 rule for the ninth character.
?

After removing spaces and hyphens, the frame must be exactly 17 characters. Letters I, O, and Q are forbidden everywhere. Position 9 (index 8) is the check symbol: decimal 0–9 or X for remainder ten. Each symbol maps to a numeric value, is multiplied by a fixed weight for its position, products are summed, and sum mod 11 must equal the check symbol’s value (X → 10).

Result

Passes check digit — weighted sum mod 11 is 10; expected X.

  • WMI (positions 1–3): 1HG
  • Attributes (4–8): BH41J
  • Check (9): X
  • Model year code (10): M
  • Plant (11): N
  • Sequential (12–17): 109186

Common use cases

  • Pre-check VIN at smog check appointment intake.
  • Fleet emissions program validating CSV before station visits.
  • Support teams fixing customer portal typos before retest fees.

Common mistakes to avoid

  • Assuming format pass means smog compliance

    Emissions results come from the tailpipe test—not checksum math.

  • Using wrong VIN from registration card vs door jamb

    Compare stickers—mismatch needs human review.

FAQ

Does smog format check run the emissions test?

No—VIN string validation only in your browser.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • vin check digit verifier online
  • validate vin number mod 11 free
  • ninth position vin checksum browser
  • iso 3779 vin check digit calculator
  • vehicle identification number check digit locally

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