A vehicle lookup starts with an identifier, and a good share of failed lookups is explained by how it was written: a zero for a letter O, an extra hyphen, a space in the middle or an old plate that no longer exists. This guide summarises how a vehicle is identified in each of the countries covered by our fine APIs and which normalisation rules to apply before sending the lookup.
Argentina: dominio
In Argentina the identifier is called dominio, although everyone says patente. Two formats coexist: the earlier one, with three letters and three digits (ABC 123), and the Mercosur one in force since 2016, with two letters, three digits and two letters (AB 123 CD). Motorcycles use their own variants with the same logic. Authorities publish the plate without spaces or hyphens, and that is what the Argentina traffic fines API expects: upper case, no separators, no zeros for Os.
Brazil: placa
Brazil has used the Mercosur plate since 2018, with three letters, a digit, a letter and two digits (ABC1D23), and the earlier format of three letters and four digits (ABC-1234) still circulates; systems convert it by replacing the second digit with the equivalent letter. Besides the plate, procedures use the RENAVAM, the national vehicle registry number, which the Brazil traffic fines API accepts as a complementary identifier when the source requires it.
Chile: patente or PPU
In Chile the single licence plate (PPU) has four letters and two digits (BBBB10) in the current format, and two letters and four digits in the earlier one (AB1234), which still circulates. Official systems accept the plate without hyphen or space; the check digit that appears on some documents is not part of the plate and must not be sent in the Chile fine lookup.
Mexico: placa and NIV
In Mexico each entity issues its plates with its own formats, three letters and three or four digits in most states, and with distinct series for private, public and federal service. Since the format is not uniform and plates are replaced with each entity’s re-plating, many sources also ask for the vehicle identification number (NIV) to confirm the unit; the Mexico fines API reports per entity which identifier each source requires.
Uruguay: matrícula
Uruguay uses a plate of three letters and four digits (ABC 1234) whose first letter identifies the department of registration, with its own series for motorcycles and official vehicles. The single vehicle revenue collection system, SUCIVE, unifies the debt lookup by plate and registration number across all departments; the Uruguay fines API accepts the plate without spaces.
Normalisation rules
- Convert to upper case and remove spaces, hyphens and dots before validating.
- Replace zeros with Os and ones with Is only in the positions the country format defines as letters, and the reverse in numeric ones.
- Validate against the current and the earlier format of the country; reject what fits neither before querying.
- Store the identifier as the user wrote it and the normalised one, to explain a failed lookup.
What the API returns
All fine APIs receive the normalised identifier in a POST, with the country implicit in the API and the jurisdictions as an optional filter, and return each infraction with the authority that recorded it and the identifier as the source publishes it. An identifier with an invalid format is rejected before querying, with the reason, so that the correction happens at the origin and not after waiting for an answer.
