NIST Atomic Spectra Database API

Access to atomic spectra data including energy levels, ionization energies, and spectral lines from the NIST Atomic Spectra Database (ASD). Provides atomic physics data for elements and their ions.

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Base URL: https://physics.nist.gov/cgi-bin/ASD/energy1.pl
Auth: none
Endpoints: 3
Reachable: yes
CORS: unknown
Last checked: 2026-03-14 16:09:15.195705

Links

Homepage: https://physics.nist.gov/PhysRefData/ASD/index.html
API Base: https://physics.nist.gov/cgi-bin/ASD/energy1.pl
Documentation:

100.0%

Uptime (7d)

674ms

Avg latency (7d)

6

Probes (7d)

Latency (7d)

Success Rate (7d)

Topics

GOVERNMENT, PHYSICS, SCIENCE

Endpoints

Method Path Summary Auth Last Status Latency
GET /energy1.pl Get energy levels for an atomic spectrum — 200 681ms
GET /ie.pl Get ionization energies and ground states — 200 654ms
GET /lines1.pl Get spectral lines (transitions) none 200 850ms