There are more genuinely usable free flight tracking APIs in 2026 than most people realise, and for a large share of projects one of them is the correct answer. We sell a paid API, so treat the recommendations here accordingly — but a customer who should have used a free feed and bought a subscription instead churns in two months and tells people we oversold them, which serves nobody.
This is the ranked list, what each is actually good at, and the specific points at which paying starts to make sense.
The short version
| Source | Cost | Best for | Main catch |
|---|---|---|---|
| OpenSky Network | Free | Research, academia, prototypes | Non-commercial terms; raw positions only |
| ADSB Exchange | Free tier + paid | Unfiltered traffic, including blocked aircraft | Rate limits; commercial use needs a plan |
| airplanes.live | Free | Hobby projects, unfiltered feed | Community-run; no availability guarantee |
| adsb.lol | Free, open | Tinkering, self-hosting, feeders | Coverage follows contributors |
| Vendor free tiers | Free up to a cap | Evaluating before buying | Small quotas; designed as a trial |
The single most important column is the last one, and the most common mistake is picking on price and discovering the catch three months in.
The free options, ranked by how often they're the right answer
1. OpenSky Network
The most established of the free sources, run as a non-profit research network fed by volunteer receivers since 2013. It archives everything, which is why so much published aviation research is built on it.
What you get: state vectors — ICAO24 hex, callsign, position, barometric and geometric altitude, velocity, track, vertical rate, squawk. Query everything or bound it to a lat/lon box.
Why it ranks first: it's stable, it's documented, it's been there for over a decade, and for the research and education use it was built for, it is simply the right tool.
The catch, and it's the one that matters: OpenSky is provided for non-commercial research and educational purposes. Commercial use needs arranging with them directly rather than being covered by the default terms. That's not a technicality to argue around — the network runs on volunteers donating coverage and on research funding. If you're putting it behind a paid product, talk to them or use something licensed for it.
There's a fuller treatment of this in OpenSky versus commercial APIs, including where teams tend to outgrow it.
2. ADSB Exchange
Known for one thing above all: it does not filter. Aircraft suppressed elsewhere through blocking programmes generally appear here, which for journalism, research and OSINT work is the entire value proposition.
What you get: live positions with wide coverage and no filtering policy applied on your behalf.
The catch: there's a free tier with rate limits and paid plans above it, and the commercial terms changed after the service was acquired. Check the current terms against your use rather than relying on what a blog post said in 2023 — including this one.
If suppressed aircraft are your reason for being here, why planes don't show on flight trackers explains what's being filtered and by whom.
3. airplanes.live
A community-run unfiltered feed that emerged as an alternative when ADSB Exchange's terms shifted. Free API access, an active contributor community, no filtering.
What you get: live positions, a straightforward API, and a culture of openness.
The catch: community-run means exactly that. There's no SLA, no support contract, and no commitment that the terms or the service will look the same next year. For a hobby project or a personal dashboard that's completely fine. For anything with customers, understand that you're a guest.
4. adsb.lol
Open in the fullest sense — open source, open data, and built around people running their own receivers and feeding back. If you're the sort of person who wants to run a receiver and see your own contribution in the network, this is the friendliest place to do it.
What you get: a free API, open tooling, and no commercial dark patterns.
The catch: coverage follows contributors, so it's excellent in some regions and thin in others. Test your specific geography rather than a global average — this matters far more than any headline coverage claim.
5. Vendor free tiers
Most commercial providers, us included, offer a free tier. Ours is 1,000 requests a month and, unlike the others on this list, needs an application rather than being self-serve.
What you get: the full commercial dataset — enrichment, support, real terms — at a volume that suits evaluation rather than production.
The catch: free tiers are trials. They're sized to let you prove the integration works, not to run a product on. Anyone telling you otherwise is selling something.
What free feeds have in common
Worth stating once rather than repeating per entry, because these apply across the board.
You get positions, not flight data. Everything above hands you an ICAO24 hex address and coordinates. None of them tells you the registration, the aircraft type, the operator, or where the flight is going, because none of that is broadcast by the aircraft. Turning 40621d into "British Airways 777 from Heathrow" is a registry join, a schedule correlation, and ongoing maintenance as aircraft change hands.
Coverage follows volunteers. Community networks are dense where enthusiasts live. Western Europe is very well covered, much of the US is excellent, and parts of Africa, central Asia and the open ocean are thin to absent. If your routes are transatlantic you may never notice; if they're West African you will notice on day one.
There's no one to call. These are non-profits and community projects. When something breaks, the correct response is patience, because nobody has promised you anything and nobody is being paid to fix it at 3am.
Terms change. Free services get acquired, restructured, or run out of funding. Building a business on terms that can change without notice is a risk that's easy to ignore until it isn't.
When you should pay
Concrete thresholds rather than vague advice. If you can answer yes to any of these, the free options have stopped being the cheaper choice.
Your use is commercial and the licence doesn't cover it. This is the clearest one. It's not about volume or features — it's that you're outside the terms. Fix it before launch, not after.
You need enrichment on every record. If your product shows aircraft type, operator or registration, you're either buying that join or building and maintaining it. Sourcing and maintaining an aircraft registry is an ongoing job, not a one-time import, and it's usually the point where the build-versus-buy sum flips. Build vs buy for ADS-B ingestion works through the actual numbers.
Something breaks if the feed is down for a day. Not "would be annoying" — breaks. Customer-facing dashboards, operational tooling, anything with a contract behind it. A research network cannot give you an uptime commitment because that's not what it is.
Someone is going to audit your data sourcing. Enterprise procurement asks for the source, its licence, its uptime commitment, and a support contact. "A volunteer research network, used outside its stated terms" does not survive that review, and by then the integration is load-bearing.
You need coverage where volunteers don't live. No amount of engineering fixes an absent receiver. If your operation is in a thin region, paid coverage is the only lever.
Your polling has outgrown the rate limits. If you're architecting around the limits — staggering, caching aggressively past the point of usefulness, running several keys — you've already spent more engineering time than a subscription costs.
A sensible path
Prototype on OpenSky or adsb.lol. It costs nothing, and if the idea doesn't work you've spent nothing finding out. We'd genuinely rather you validated the concept free than bought a subscription for something abandoned in three weeks.
Then ask the four questions that actually decide it: is this commercial, do I need enrichment, where do I need coverage, and what breaks if it's down. If the answers point at free, use free. If they point the other way, the thing you're buying isn't the ADS-B — everyone decodes the same broadcasts — it's the registry join maintained for you, coverage bought rather than hoped for, an uptime commitment with someone accountable, and a licence your legal team can read.
Our free trial is 1,000 requests a month and enough to test enrichment against your own data before committing. For the wider comparison including paid options, aviation data APIs in 2026 covers pricing, coverage and latency side by side, and what free flight tracking APIs actually give you goes deeper on where the limits bite.