Directory / physics.openverbs.com
List every physical constant in the dataset, or only those in a given category (universal, adopted, electromagnetic, atomic, physico-chemical). Returns the constants, the total count and the set of available categories.
# 1. Ask the endpoint what it costs (no payment, no wallet needed): curl -i -X GET 'https://physics.openverbs.com/v1/list' # -> HTTP/1.1 402 Payment Required # the response carries the price, asset and pay-to address. # 2. Pay and retry with any x402 client: npx x402-fetch 'https://physics.openverbs.com/v1/list'
Endpoint: https://physics.openverbs.com/v1/list. Operated by physics.openverbs.com, not by Animica. Price and availability were correct at the last probe on 2026-10-01 and are set by the operator, who may change them.
Look up a physical constant by its key (e.g. "speed-of-light"), symbol (e.g. "c") or exact name. Returns the CODATA 2018 recommended value, unit, relative stand…
Search the constants table by key, symbol or name substring. Exact matches rank first, then prefix matches, then substring matches. Returns up to `limit` consta…