The free SpaceNexus API

Plans and limits

Which plan a key runs on follows its owner's paid subscription at the moment of the call: upgrade and the same keys get the Professional limits at once; if a subscription ends, or during a free trial, the keys run on the free plan, and on the free plan only your 2 oldest active keys work (others answer 403 KEY_OVER_PLAN_LIMIT). Minute, day and month limits are UTC clock windows. They count per key and, at the per-key limits times the key cap, across all your keys together, revoked and rotated ones included, so new keys never reset a budget. Successful answers, 429s and 403s all say which plan answered in the X-API-Plan header. Past a limit you get a 429 with Retry-After; a free key calling a Professional endpoint gets a 403 with the code SUBSCRIPTION_REQUIRED.

No key at all? The open JSON feeds need none (60 requests a minute per IP), and every dataset downloads as CSV or JSON without an account (30 files per 10 minutes per IP).

Using an AI assistant? The same keys work with the SpaceNexus MCP server: its open tools need no key, a free key adds launch_ledger_record, promise_ledger_entries and dataset_links, and a Professional or Research key adds funding_round_history. Keyed MCP calls count against the same per-key limits as the calls above.

Get started

1. Create a free account (or sign in).
2. Verify your email address (the link in your welcome email), then open My Desk, API keys and create a key. It is shown once: copy it then. We store only a SHA-256 hash of it, so we cannot show it again; if you lose it, rotate it (the key keeps its usage and limits; only the secret changes).
3. Send it as Authorization: Bearer snx_... or X-API-Key: snx_..., from a server or a script, never from a web page.

curl "https://spacenexus.us/api/v1/launches?limit=5" \
  -H "Authorization: Bearer snx_YOUR_API_KEY"

import requests

r = requests.get(
    "https://spacenexus.us/api/v1/executive-moves",
    params={"limit": 10},
    headers={"X-API-Key": "snx_YOUR_API_KEY"},
    timeout=30,
)
r.raise_for_status()
for row in r.json()["data"]:
    print(row["date"][:10], row["personName"], row["moveType"], row["sourceUrl"])

// Server-side only: never ship a key to a browser.
const res = await fetch('https://spacenexus.us/api/v1/space-weather', {
  headers: { Authorization: `Bearer ${process.env.SPACENEXUS_API_KEY}` },
});
if (res.status === 429) {
  console.log('Rate limited; retry after', res.headers.get('Retry-After'), 's');
}
const { data } = await res.json();

Endpoints

Parameters and response shapes for each are in the free OpenAPI spec; the API reference adds worked examples. Research exports (full history, portfolios, screens) are part of SpaceNexus Research and are not in the API.

Licence and attribution

SpaceNexus data is CC BY 4.0: use it in anything, commercial or not, as long as you credit it. Wherever you show or publish it, put “Data: SpaceNexus (spacenexus.us)” with a link to spacenexus.us (in an app's about screen, a chart caption or a notebook's sources). Facts we take from others are not ours to license, and we never relabel them:

• /api/v1/launches: Launch facts from Launch Library 2 by The Space Devs: credit them; not relicensed by SpaceNexus.
• /api/v1/launch-vehicles: SpaceNexus compilation, CC BY 4.0.
• /api/v1/companies: SpaceNexus compilation, CC BY 4.0. No stock quote data.
• /api/v1/executive-moves: SpaceNexus compilation, CC BY 4.0; each row links its primary source.
• /api/v1/space-weather: NASA DONKI (flares, storms, CMEs) and NOAA Space Weather Prediction Center (Kp) data, US government works, summarised by SpaceNexus.
• /api/v1/satellites (Professional): Satellite data from GCAT (J. McDowell, planet4589.org/space/gcat), CC BY 4.0. Credit GCAT; not relicensed by SpaceNexus.

Terms of the free API

• Keys are personal to your account. Keep them secret and server-side. You can rotate or revoke a key at any time from My Desk; a revoked key stops working at once.
• Stay within the limits. Do not open extra accounts or share keys to get around them; cache answers on your side instead. Keys used to get around the limits, or to overload the service, may be revoked.
• The data you receive stays under its licence: CC BY 4.0 for ours, with the attribution above, and the provider's own terms for credited third-party facts.
• The free API is provided as is, without an uptime guarantee. Numbers carry their sources and dates; check anything you rely on, and report errors.
• If the limits or these terms change, this page is updated, with the date.
• Money never touches the data: no response has a sponsored row, a paid field or a paid order, on any plan. The site's general terms of service also apply.

Last updated 26 September 2026.