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Finland Y-tunnus Validator

Online validator for Finnish Business ID (Yritys- ja yhteisötunnus / Y-tunnus) with Modulo 11 check.

About the Yritys- ja yhteisötunnus (Y-tunnus)

Finnish business registry identification code.

Supports both hyphenated and non-hyphenated formats.

Finnish Y-tunnus Anatomy & Structure

The Business ID follows the standard format NNNNNNN-T (8 characters):

PositionFieldLengthRule & MeaningExample
1 to 7Base Company Number7 digitsSequential number issued by PRH or Tax Administration0112038
SeparatorHyphen1 charStandard delimiter-
8Check Digit1 digitWeighted Modulo 11 integrity digit9

Official Algorithm (Modulo 11 PRH / Vero)

Official formula governed by Finnish Business Information Act (272/2001):

Sum = Σ (d[i] * W[i]) [W = 7, 9, 10, 5, 8, 4, 2]; Remainder = Sum mod 11; DV = Remainder === 0 ? 0 : 11 - Remainder.
  1. 1. Take first 7 base digits.
  2. 2. Multiply by weights [7, 9, 10, 5, 8, 4, 2].
  3. 3. Compute sum and remainder modulo 11.
  4. 4. Check validity: remainder 1 is invalid; 0 yields 0; otherwise 11 - remainder.
  5. 5. Compare with digit 8.

Frequently Asked Questions (FAQ)