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Immigration, Visa & Travel DocumentsGenerated accuracy model review: 2026-05-06

Schengen 90/180 Day Calculator accuracy and testing

This page documents how Calwarden builds trust for this calculator: source notes, regression-style default tests, limitations, assumptions, unit handling, rounding, and visible change history.

Formula source

  • Window start = reference date - window days + 1. Used days = inclusive stay days overlapping the window. Remaining days = allowed days - used days.

Test cases

Default input regression check

Generated from the checked-in default inputs and calculate function.

Inputs

  • Reference Date: 2026-05-01
  • Stay 1 Entry Date: 2026-02-01
  • Stay 1 Exit Date: 2026-02-20
  • Stay 2 Entry Date: 2026-03-15
  • Stay 2 Exit Date: 2026-04-05
  • Stay 3 Entry Date: 2026-04-20
  • Stay 3 Exit Date: 2026-04-28
  • Allowed Days: 90 days
  • Rolling Window: 180 days

Expected outputs

  • Estimated Remaining Schengen Days: 39 days
  • Estimated Used Schengen Days: 51 days
  • Window Start Date: 2025-11-03

Known limitations

  • This calculator does not account for nationality-specific exemptions, long-stay visas, residence permits, bilateral agreements, enforcement discretion, or official border-system records.

Assumptions

  • The model counts stay days inclusively for entry and exit dates.
  • The rolling window ends on the reference date and includes that date.
  • This is a planning estimate only, not legal advice, not an official immigration, travel, school DSO, USCIS, CBP, consulate, employer, or government determination.

Unit handling

  • Reference Date accepts calendar dates.
  • Stay 1 Entry Date accepts calendar dates.
  • Stay 1 Exit Date accepts calendar dates.
  • Stay 2 Entry Date accepts calendar dates.
  • Stay 2 Exit Date accepts calendar dates.
  • Stay 3 Entry Date accepts calendar dates.
  • Stay 3 Exit Date accepts calendar dates.
  • Allowed Days accepts values in days.
  • Rolling Window accepts values in days.
  • Estimated Remaining Schengen Days is displayed in days.
  • Estimated Used Schengen Days is displayed in days.

Rounding rules

  • Number displays use up to 2 decimal places in the calculator UI.
  • Input precision follows configured step values where provided.

Version history

1.0.0 - 2026-05-06

Generated accuracy and testing page from the current schengen-90-180-day-calculator calculator definition.

Change log

2026-05-06

Published default regression test documentation and metadata fallbacks for Schengen 90/180 Day Calculator.

Calculator transparency

Accuracy pages are generated from checked-in calculator definitions and can be upgraded with curated review metadata over time.

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