Utilities
Assorted calculators and generators for everyday work: date maths, cron expressions, mock data, Mexican test IDs and robots.txt, right in your browser.
5 tools
Date and Age Calculator
Your exact age in years, months and days, the months and days between two dates, how many days 2 years and 5 months are, and which year you were born. No signup.
OpenMexican Test Data Generator
Generate fictitious RFC, CURP, CLABE and NSS with correct check digits to seed development environments and tests. Export to JSON, CSV or SQL. No server involved.
OpenWhatsApp Business API Cost Calculator
From 1 October 2026 Meta charges 0.1565 MXN per service message from the 1,001st of the month (1,000 free per number) and 0.7298 MXN per marketing message. Work out your monthly bill and compare it with the July rate card. No sign-up.
OpenMock Data Generator
Generate realistic mock data (names, emails, dates, UUIDs, numbers and more) with a configurable schema and export to JSON or CSV. All in your browser.
Openrobots.txt Generator
Build your site's robots.txt with per-robot rules (Allow, Disallow, Crawl-delay) and sitemaps, with quick templates. Copy or download instantly.
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