idcheck.now
IL · Driver's license verification

Verify Illinois driver's licenses

Capture a Illinois license front and back and idcheck.now decodes the AAMVA PDF417 barcode, validates the 1 letter + 11–12 digits (state ID: digits first, letter last) license number by recomputing it from the holder's name and birthdate, and cross-checks every encoded field against the printed card.

AAMVA v01–v12 Soundex + DOB recomputation DLDV add-on
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What we check

Every layer we run on a Illinois license

These checks run on every Illinois verification — no per-feature upsell on the core flow.

  • AAMVA PDF417 decode

    Full CDS v01–v12 parse of the Illinois barcode — decoded live in the browser and again independently server-side. Any mismatch is a tamper signal.

  • Mandatory-field enforcement

    DCS, DAC, DBB, DBA, DAQ, and address elements must be present and well-formed per the AAMVA CDS.

  • License-number recomputation

    The Illinois number is recomputed from the holder's surname (Soundex), first/middle name codes, birth year, and day code — then compared to the barcode's DAQ field segment by segment.

  • Barcode ↔ OCR cross-check

    Encoded fields are compared against the printed visual zone — name, DOB, expiry, and license number must agree.

  • Expiry & age validation

    DBA (expiration) is enforced against the validity window; DBB (birth date) drives per-session age thresholds.

  • Issuing-authority IIN check

    The issuer identification number in the barcode header is checked against Illinois's AAMVA issuer record.

  • DMV verification (DLDV add-on)

    Illinois participates in AAMVA DLDV — a live check of license number, name, and DOB against the state DMV record, enableable as an add-on.

License-number format

The Illinois license-number format

1 letter + 11–12 digits (state ID: digits first, letter last)

The barcode's DAQ element carries the license number. idcheck.now validates it against the published Illinois pattern as a plausibility signal — formats drift over time and legacy cards remain in circulation, so a format miss is a warning fed into the composite score, not an automatic decline.

For Illinois, this is only the first step: the number is also recomputed from the holder's identity — see the deep dive below.

Fraud deep dive

Illinois license numbers encode name and birthdate

SSSS FFF Y Y DDD

Illinois uses the same Soundex-derived scheme as Florida and Wisconsin: the first four characters are the Soundex code of the surname, followed by a three-digit first-name + middle-initial code from the Gallian table, then the two-digit birth year.

The Illinois day code is (month − 1) × 31 + day, with 600 added for female holders — a different multiplier and offset than Florida and Wisconsin. Illinois state ID cards use a variant layout that moves the leading letter to the end; we normalize that layout before recomputing.

Because the day-code multiplier differs by state, a number generated with the Florida formula won't pass as an Illinois number. idcheck.now applies the Illinois-specific scheme and flags any mismatch.

Inside the barcode

What the Illinois PDF417 barcode tells us

A sample of the AAMVA CDS elements decoded from every Illinois barcode, and what each one feeds into.

ElementMeaningHow idcheck.now uses it
DAQ Customer ID / license number The license number itself — validated against the state format and, for FL/IL/WI/MO, recomputed from the holder's identity.
DCS Customer family name Mandatory. Soundex-encoded into the license number in FL/IL/WI; cross-checked against the printed card everywhere.
DAC Customer first name Mandatory. Mapped to a first-name code (Gallian table) inside FL/IL/WI license numbers.
DBB Date of birth Mandatory. Encoded into the FL/IL/WI day-code segment and the Missouri trailing digits; drives age checks.
DBA Document expiration date Mandatory. Enforced against the document validity window on every verification.
State DMV verification

AAMVA DLDV for Illinois

DLDV participant

Illinois participates in AAMVA's DLDV program. As an add-on, idcheck.now can submit the license number, name, and date of birth to the Illinois DMV through DLDV and return the state's own verdict — the strongest confirmation short of an in-person check.

Most US jurisdictions participate in DLDV; participant lists and response fields change over time. Confirm availability for Illinois at integration time.

FAQ

Illinois verification questions

What format is a Illinois driver's license number?

Illinois driver's license numbers are 1 letter + 11–12 digits (state ID: digits first, letter last). idcheck.now validates the barcode's DAQ field against this pattern on every verification; older card layouts still in circulation are handled as plausibility warnings rather than hard failures.

Can a fake Illinois license number pass idcheck.now?

Not easily. Illinois derives license numbers from the holder's surname (Soundex), first and middle names (Gallian code table), birth year, and a birth-date day code that also encodes sex. idcheck.now recomputes the expected number from the barcode's name and DOB fields and compares it segment by segment — a fabricated number that wasn't derived from the claimed identity fails the check.

Verify Illinois licenses in your onboarding flow today.

Your first 100 verifications are free. No credit card — five lines of JavaScript.

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