Equivalence across jurisdictions

A UK 2:1 is not a Hong Kong cGPA is not a Taiwanese percentage. The rules are public, contested, and nowhere written down together. This is the smallest working version of a problem that recurs in holidays, visas, tariffs and qualifications.

Problem

Three scales, three different instruments, no authoritative mapping

Approach

Match by band position, never by arithmetic

Role

Designer-builder

Status

Working demonstration · sources declared per row

Try it

Why it refuses to give you a number

The obvious build converts a mark to a mark: 68% becomes a 3.3 becomes a 78. That would be false precision. The three instruments are structurally different — the UK awards an honours classification off a percentage, Hong Kong runs a 4-point cGPA and an inherited honours classification, Taiwan uses a 100-point scale with a pass at 60 — and no arithmetic maps between them without inventing information the source systems never carried.

So the tool matches by band position and shows the whole band, which is the strongest true statement available. Where the mapping is not sourced, it is flagged ▲ unverified rather than asserted quietly. Hong Kong is the interesting case: HKU, CUHK, HKUST and PolyU do not agree with each other, so a single authoritative HK row does not exist and the tool should not pretend otherwise.

What it demonstrates

The same operation as timesys.pro at 241 jurisdictions, and as the HSBC analysis across two regulators: making systems comparable without flattening the differences that make them incompatible in the first place. Naming what cannot be converted is the deliverable.