Methodology
How TTDI compiles the four-government travel advisory tracker. Hand-written; the daily pages add no model-generated prose.
What this tracker is
A daily snapshot of official travel advice from four governments - the United States, the United Kingdom, Canada, and Australia - placed side by side on one 1–4 scale. Each row quotes the government's headline wording, links to the government's page, and records when that page was last updated. Australia is included here; the advisory panel on ttdi.net city pages currently shows the US, UK and Canada only.
The 1–4 scale
Level 1 = normal / standard precautions. Level 2 = heightened caution (or, for the UK, advice against travel to parts of the country). Level 3 = reconsider / avoid non-essential travel. Level 4 = do not travel / avoid all travel. The UK FCDO scale has no whole-country level 2; when FCDO advises against all travel to parts of a country, that row is recorded as level 2 with regional=yes.
Sources
US: travel.state.gov Travel Advisories API. UK: GOV.UK content API for foreign-travel-advice (alert_status tokens). Canada: travel.gc.ca index-alpha JSON (advisory-state 0–3 mapped to 1–4). Australia: Smartraveller destinations export. Fetches run daily at 20:30 ICT; this site is rebuilt from that batch shortly after 21:00 ICT.
What is left out
Meta pages that are not destinations (for example Australia's "Crisis alert" and "No travel advice"), and combined pages that cover more than one ISO territory under a single title, are omitted and listed in skipped.csv inside the day's data folder. Sub-national pages that do resolve to one ISO code (West Bank and Gaza → PS; Bonaire → BQ) appear under that code.
Disagreement view
The index ranks destinations by the gap between the highest and lowest of the four levels that day. A gap of three means one government is at level 4 and another at level 1. Gaps reflect different mandates and update cadences; they are not a verdict.
Licence and citation
Government wording remains under each government's terms. The compiled CSV/JSON and these pages are published by TTDI for research citation. Canonical URLs live under https://ttdi.net/research/advisory-tracker/.