Online tools for developers

Check the mathematical consistency of a CPF with immediate feedback.

Validate the mathematical structure of CNPJ numbers in numeric or alphanumeric format.

Validate alphanumeric CNPJ values with or without mask and check verifier digits.

Validate Brazilian State Registration numbers by state, with support for SP, MG, and RJ.

Online state registration validator for sp for developers, QA, and browser-based testing.

Online state registration validator for mg for developers, QA, and browser-based testing.

Online state registration validator for rj for developers, QA, and browser-based testing.

Validate CNH format and verifier digits for registration tests.

Validate RENAVAM format and verifier digit without checking official vehicle data.

Validate Mercosur and old Brazilian license plate formats.

Generate valid CPF numbers for software tests in seconds, with or without formatting.

Generate valid CNPJ numbers for tests in numeric or alphanumeric format.

Generate valid alphanumeric CNPJ values for tests, with letters and numbers in the first 12 positions.

Generate fictional Brazilian person data with a valid CPF for tests and JSON output.

Generate a fictional Brazilian company with valid CNPJ, contact, and address for test environments.

Generate fictional card numbers that pass Luhn checks for tests.

Generate UUID v4 and ULID identifiers for tests, fixtures, and seed scripts.

Generate random passwords in the browser with privacy-focused controls.

Convert days, hours, minutes, seconds, milliseconds, and ticks into a readable duration.

Run regular expressions locally against sample text and inspect matches.

Read simple XSD elements and generate an initial XML example.

Decode JWT header and payload locally without sending tokens to a server.

Encode and decode URLs and query strings directly in the browser.

Generate MD5, SHA-1, SHA-256, and HMAC SHA-256 hashes locally.

Compare two JSON documents and see added, removed, and changed fields.

Encode text to HTML entities and decode HTML entities back to plain text.

Validate classic crontab expressions and use common scheduling templates.

Encode and decode Base64 text with instant local feedback.

Format JSON, XML, and YAML with immediate readability and syntax highlighting.

Edit Markdown with a local preview for documentation, issues, and technical notes.

Render and export Mermaid diagrams as SVG or PNG.

Validate and decode Pix Copy and Paste payloads with CRC and main EMV fields.

Generate Pix Copy and Paste payloads for tests and homologation with a fictional key.

Validate Pix key formats for CPF, CNPJ, email, phone, or UUID.

Validate boleto digitable line blocks, verifier digits, and basic data.

Convert a boleto digitable line to a barcode and back.

Convert monetary amounts to written text in Brazilian Portuguese.