About 183333
183333.com is an independent educational project for people whose lives cross borders. We build free, private tools for counting days and testing residency rules, and we write plain-English guides that point back to the law.
Why the name
The domain reads as 18 · 3333, and we read it as 183 · 3 · 3 · 3: the 183-day threshold used by many tax systems, a three-year look-back, three residency tests, and three proofs for every stay. The number is our domain and our mnemonic — not a claim to any trademark, and not a reference to any official programme.
What we believe
- Tools before opinions. Every calculator shows how it reached its answer.
- Sources over hearsay. Every country summary links to the official authority.
- Privacy by default. Your trips stay in your browser.
- Independence. Advertisers and sponsors never edit rules or calculator logic.
How we keep content accurate
Country summaries are reviewed on a rolling schedule and dated. Readers can report outdated rules, and corrections are prioritised. Our guides are educational — for advice, use our free matching service to reach a qualified professional.
How we are funded
Through Google AdSense advertising, labelled sponsorships, referral fees from independent professionals, and reader support.