What is the correct CEP format?

A CEP is eight digits written as NNNNN-NNN, for example 01310-100. The validator strips any spaces or hyphens, confirms there are exactly eight digits, and re-formats the value with the standard hyphen.

How does the tool know the state from a CEP?

Correios assigns CEP ranges by the leading digits: the first digit sets a macro-region and the first two digits narrow it to a state or area. The tool matches your prefix against those published ranges to report the likely UF.

Does this look up the exact street address?

No. It validates the format and identifies the region from the prefix, fully offline. For the precise street, neighbourhood, and city, query the official Correios Busca CEP service or a CEP API.

Why might the state show as a pair like PA/AC?

Some two-digit prefixes span more than one state because Correios grouped neighbouring areas into a single range. In those cases the tool lists every state the range covers rather than guessing one.

Is the CEP sent anywhere?

No. The check runs entirely in your browser, so the postal code you enter never leaves your device. That makes it safe for validating customer addresses in bulk during checkout.

Brazil CEP Postal Code Validator

Validate a Brazilian CEP and find its region instantly

The CEP (Código de Endereçamento Postal) is Brazil’s eight-digit postal code. At checkout, a malformed CEP breaks shipping-rate calls and address autofill. This validator confirms the format and, from the leading digits, tells you which state or area the code belongs to — without any network request.

How it works

A CEP is structured NNNNN-NNN. The leading digits are meaningful: Correios divides the country into ten macro-regions by the first digit, then subdivides by the next digits. The tool:

Strips non-digits and confirms exactly eight digits are present.
Re-formats the value as NNNNN-NNN.
Reads the first two digits as a prefix and matches it against the published Correios range table to identify the state (UF) and area.

For example, prefixes 01–05 are São Paulo capital, 20–23 are Rio de Janeiro capital, and 90–99 are Rio Grande do Sul.

Example and notes

The CEP 01310-100 (Avenida Paulista, São Paulo) has prefix 01, so the tool reports SP, São Paulo capital. A code like 90010-150 has prefix 90, mapping to Rio Grande do Sul.

Treat the region result as a strong hint, not a precise address. Prefix ranges identify the state reliably, but the exact street and neighbourhood require the official Correios lookup. Some prefixes legitimately cover more than one state, which the tool shows as a grouped UF.