residex.ioEvery trip accounted forThe 183-Day Rule Explained
Understand and track the most common tax residency threshold worldwide
What is the 183-Day Rule?
The 183-day rule is a tax residency test used by most countries. If you spend 183 days or more in a country during a tax year, you may become a tax resident and owe taxes on your worldwide income.
Who Needs to Track This?
- Digital nomads working remotely across countries
- Frequent business travelers
- Expats splitting time between countries
- Consultants with international clients
- Students studying abroad
Why Track Your Days?
Avoid Surprises
Know before you accidentally trigger tax residency
Visual Tracking
See your travel patterns at a glance
100% Private
Data stays on your device, no account needed
Past 183 Days — Then What?
residex.io tells you exactly where you stand against the 183-day line and warns you before you cross it. But the rule itself is the easy part. Crossing 183 days doesn’t tell you what you actually owe, whether a tax treaty offers relief, which forms to file, or how it interacts with residency you may already hold elsewhere.
That’s where Amanda picks up. Amanda turns your day count into a clear read on your real cross-border obligations, so crossing a threshold doesn’t become an unexpected tax bill.
Start Tracking Your 183-Day Risk
Free forever. No account required. Your data never leaves your device.
How residex.io works
residex.io tracks where you have physically been, and tells you where that puts you against each country's own residency threshold.
What it does: • Counts your days per country, and per area for the Schengen 90/180 rule • Applies each country's actual rule — 183 days for most, 180 for Thailand, the UK's 6 April tax year, Portugal's rolling twelve months, and the US weighted three-year test • Counts days the way each rule counts them, including the arrival and departure days that most tests count and a nights-based tally misses • Warns as you approach a threshold, and can notify you on the date a trip you have already planned would take you across it • Exports to CSV, or hands off to Amanda for the compliance picture
Built for digital nomads, frequent travellers, expats, and anyone whose year is split across borders.
On your device, and nowhere else. There is no account, no login, and no copy of your travel history on our servers — residex works offline because the data never needed to be anywhere else.
It leaves your device only when you decide to send it: • A backup file you save yourself • A transfer to another device, encrypted with a code only you hold — the server relaying it cannot read what it is carrying • A hand-off to Amanda, which you start
We do receive a small amount of anonymous usage information — how many trips are in a log, how old an install is, the language the app is used in, and a random identifier that is not linked to you. Never a trip, a date, a destination, or your name. It is listed in full in our Privacy Policy.
The trade-off worth knowing: because your device holds the only copy, clearing your browser data or deleting the app erases it, and we cannot restore it. Save a backup before you switch devices.
No — residex is a day counter, not a compliance engine. It flags when you cross a threshold like the 183-day rule, but turning that into specific filings, tax exposure, or reporting obligations depends on your jurisdictions and personal ties.
For that, our partner Amanda maps your full cross-border legal exposure across countries, surfaces the filings and deadlines you trigger, and turns the data residex collects into a concrete compliance picture you can hand to your accountant.
You can export your residex trips and import them straight into Amanda — the CSV formats are aligned.