RFC Generator
GeneratorGenerate valid Mexican RFC numbers for testing. Supports both personal (13 chars) and business (12 chars) RFC formats. Runs entirely in your browser.
⚠ For testing purposes only. The homoclave is randomly generated — not SAT-issued.
About this tool
About RFC Generator
RFC (Registro Federal de Contribuyentes) is Mexico's federal taxpayer identification number, issued by the SAT (Servicio de Administración Tributaria). Personal RFCs are 13 characters (4 name-derived letters + 6-digit date + 3-char homoclave); business RFCs are 12 characters (3 name-derived letters + 6-digit date + 3-char homoclave). The homoclave is an internal SAT code that distinguishes individuals with the same name+date combination — for test data, a random 3-char string is sufficient.
The personal RFC generator applies the official SAT algorithm: extracts the first initial and first internal vowel of the paternal surname (2 chars), the first initial of the maternal surname, and the first initial of the first name. Compound first names (María, José) use the second name. Date is encoded as YYMMDD. The business generator takes the first 3 characters of the company name after stripping common legal suffixes (SA de CV, etc.).
RFC validation and generation are essential for Mexican tax system integrations, payroll software, SAT API calls, invoice (CFDI) generation, accounting software, KYC flows for financial services, and any Mexican e-commerce platform that collects fiscal data.
Instant RFC generation from name and date inputs, with the official SAT extraction rules applied. The random fill button generates realistic Mexican names and dates for quick test data. The homoclave is randomly generated — realistic for test data but not the same as the SAT-issued value. All computation runs in the browser.
Key Features
- Personal RFC: official SAT 4-letter name extraction algorithm
- Business RFC: 3-letter company name extraction
- Both types: YYMMDD date encoding
- Random homoclave for test data
- Random fill with realistic Mexican names and companies
- Disclaimer: test data only, not SAT-registered
FAQ
RFC Generator — Frequently Asked Questions
What is an RFC in Mexico?
RFC (Registro Federal de Contribuyentes) is Mexico's federal taxpayer registration number, issued by the SAT (Tax Administration Service). Every individual and legal entity that performs economic activities in Mexico is required to have an RFC. It is used on all tax documents, invoices (CFDI), payroll slips, bank accounts, and most official transactions.
What is the difference between a personal and business RFC?
A personal RFC (persona física) is 13 characters: 4 letters derived from the person's name + 6-digit birth date + 3-character homoclave. A business RFC (persona moral) is 12 characters: 3 letters from the company name + 6-digit constitution date + 3-character homoclave. The homoclave is assigned by the SAT and cannot be derived from the name alone.
What is the homoclave?
The homoclave is the last 3 characters of the RFC, assigned by the SAT to distinguish taxpayers whose name+date combination would otherwise produce the same RFC. The first two homoclave characters are alphanumeric (A-Z, 0-9); the third can also include a digit. Since the official homoclave algorithm is proprietary to the SAT, this generator produces a random 3-character string — suitable for test data but not identical to what the SAT would issue.
Are generated RFCs real?
No. The RFCs produced by this tool follow the official format and naming rules but are not registered with the SAT. The homoclave is random — not the SAT-computed value. Generated RFCs will pass format validation but will fail against the SAT's registration database.
Tips
- The maternal surname is optional — leave it blank and the generator uses 'X' as placeholder
- The RFC distinguishes María (goes to next name) from other compound first names
- Use the random fill to quickly get realistic-looking Mexican RFC test data
- Validate your generated RFC with the RFC Validator tool