Observed arrival · 2026-10-10
Metrology Graph maps the tangled ancestry of units
An interactive graph traces how measurement units are defined, related, and changed over time.
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✦Pretty
●Pro
◎Niche
◉Human
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ƒJS
- For
- Readers tracing unit definitions and comparing measurement systems
- Worth noticing
- Red loops flag circular definitions, including the ampere–coulomb relationship; the graph is generated from YAML data on GitHub.
Field notes
The graph places units in levels according to the deepest unit each depends on, rather than simply reproducing the familiar SI base/derived split. It marks circular definitions in red; the page gives the ampere–coulomb relationship as an example. Its data is generated from YAML on GitHub, and a static Graphviz diagram is also linked as a separate view.
Observed signals
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
✦PrettyNotable craft visible
●ProPolished or operationally mature
◎NicheUnusually specific use
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