science-and-math APIs

arcsecond.io is a free astronomy API that aggregates data from multiple space databases, including stars, planets, exoplanets, and observing sites.

arXiv provides programmatic access to curated research-sharing platform: physics, mathematics, quantitative finance, and economics via REST API.

CORE provides access to millions of open-access research papers from repositories and journals worldwide.

GBIF (Global Biodiversity Information Facility) is a free, open API providing access to hundreds of millions of species occurrence records from around the world.

iDigBio is a free API that gives you access to millions of digitized natural history museum specimens from institutions across the United States and beyond.

INSPIRE-HEP is a free REST API for the High Energy Physics literature database, covering papers, authors, institutions, conferences, and experiments in particle physics.

isEven is a humorous free API that tells you whether a number is even or odd.

ISRO is a free, no-auth API that provides detailed information about the Indian Space Research Organisation spacecraft and missions.

ITIS (Integrated Taxonomic Information System) is a free API providing authoritative taxonomic data on plants, animals, fungi, and microbes.

Launch Library 2 is a free, comprehensive API for spaceflight launches, rockets, missions, and events maintained by The Space Devs community.

The Materials Platform for Data Science (MPDS) API provides access to curated experimental data about materials — things like crystal structures, physical properties, and phase diagrams.

The Minor Planet Center API (via Asterank) gives you access to data about asteroids, comets, and other small solar system bodies.

The NASA API provides free access to a huge collection of NASA data including the Astronomy Picture of the Day (APOD), Mars rover photos, near-Earth asteroid data, and satellite imagery.

NASA ADS (Astrophysics Data System) is a digital library for astronomy and physics research papers, with millions of articles going back decades.

Newton is a free microservice API that performs symbolic and arithmetic math calculations — from simplifying expressions to computing derivatives and integrals.

NoctuaSky is a sky observation platform and its API gives you access to astronomical data like star positions, constellations, and celestial events.

The Numbers API from math.tools provides facts, trivia, and mathematical data about numbers — including the number of the day, random numbers, and detailed number properties.

Numbers API (numbersapi.com) returns interesting facts about numbers — mathematical, date-based, year-based, or trivia facts.

Ocean Facts provides programmatic access to facts pertaining to the physical science of oceanography via REST API.

Open Notify provides real-time data about the International Space Station (ISS) — including its current location, the astronauts currently aboard, and pass times over your location.

The Open Science Framework (OSF) API gives you access to a large open repository of research materials, datasets, preprints, and study designs from researchers around the world.

Purple Air gives you access to real-time air quality data from a global network of community-owned sensors.

Remote Calc is a simple API that accepts a base64-encoded mathematical expression, decodes it, and returns the computed result as JSON.

SHARE is an open dataset API that aggregates metadata from hundreds of research repositories and academic publishers worldwide.

The SpaceX API is an open-source REST API providing detailed data about SpaceX launches, rockets, capsules, launchpads, and crew.

SpaceX provides programmatic access to graphql, company, ships, launchpad and launch data via REST API.

The Sunrise and Sunset API returns accurate sunrise, sunset, solar noon, and day length data for any latitude/longitude coordinate on Earth.

Times Adder is a lightweight utility API that accepts an array of time values and returns their total sum.

The TLE API provides up-to-date orbital data for satellites currently orbiting Earth, sourced from NORAD datasets.

The USGS Earthquake Hazards Program API provides real-time and historical earthquake data from seismic monitoring stations around the world.

USGS Water Services provides real-time and historical data on streamflow, water levels, and water quality for thousands of monitoring stations across the United States.

The World Bank API provides access to thousands of development indicators covering economics, education, health, and infrastructure for over 200 countries spanning decades.

xMath provides programmatic access to random mathematical expressions via REST API.