What these tools do
They apply published day-counting rules to dates you enter and show the arithmetic. That is genuinely useful, and it is the entire scope of what they do.
What they cannot do
Immigration and tax residency outcomes rarely turn on days alone. A calculator cannot see, and does not account for:
- your nationality, visa type, residence permit or immigration history;
- bilateral agreements that may modify a rule for your passport specifically;
- double tax treaties and their tie-breaker provisions;
- tests based on your permanent home, family, or centre of economic interests, which can establish residency on very few days;
- discretion exercised at the border, which is broad and not appealable in the moment;
- exemptions, reliefs and anti-avoidance rules that may apply to your circumstances;
- rule changes made after this site was last updated.
Specific limitations by tool
Schengen 90/180
Applies the standard rule only. It ignores bilateral visa waiver agreements, whose legal status is disputed and whose treatment varies by member state, and it does not account for time spent under a national long-stay visa or residence permit.
US Substantial Presence Test
Performs the weighted arithmetic on the days you enter. It does not determine whether particular days are excludable, whether you qualify as an exempt individual, whether a treaty tie-breaker applies, or how first-year and last-year residency rules affect you. US tax residency carries substantial reporting obligations with severe penalties, so professional advice is strongly recommended.
UK Statutory Residence Test
Implements the day counts and the sufficient ties bands. It relies on your own declarations for full-time work, the UK home test and each individual tie, because those turn on detailed facts. It does not apply split-year treatment, the deeming rule, or exceptional-circumstances relief.
Tax residency day tracker
Uses simplified primary day-count triggers. Most countries combine their day count with other tests, several have additional limbs this tool does not model, and thresholds change. Treat a breach as a prompt to seek advice.
Thailand and Japan counters
Per-entry allowances vary by nationality and change. Cumulative annual figures shown for immigration purposes reflect practice and officer discretion rather than a published statutory limit, and are labelled as such on those pages.
Accuracy and updates
We try to keep these rules current and to test the arithmetic thoroughly, but we cannot guarantee that any figure is accurate or up to date. Rules change without notice. If you spot an error, please tell us via the contact page — corrections are welcome and acted on.
Affiliate disclosure
Some pages contain affiliate links inside clearly labelled recommendation blocks. If you buy through one we may earn a commission at no extra cost to you. This never affects the output of a calculator, and recommendation blocks are always visually separated from results.
Your responsibility
You are responsible for your own compliance. Before making a decision that depends on a day count — booking travel, filing a return, or claiming a residency position — verify it against an official source or with a qualified professional.