# Best pay-per-call flight search APIs for AI agents (October 2026)

> Zero indexes 8 pay-per-call services for flight search: 8 of the 8 ranked here answered a live probe in the last 7 days, quoted from $0.01 to $0.1 per call (median $0.02) over MPP or x402 with no API key; the cheapest live option is FlightAware Flight Info by Ident at $0.01. The one with real agent usage in the last 30 days is SerpApi Google Flights Search. Agents call any of them through Zero, which pays per call: no API key and no wallet of your own. New accounts start with $5.

Canonical page: https://www.zero.xyz/use-cases/flight-search
Ranked by evidence from Zero's own probes and real agent calls. Updated Oct 31, 2026. 11 agents searched Zero for this in the last 90 days.

## Ranked services

| # | Service | Host | Price | Rail | Live | Calls 30d | Reviews |
|---|---|---|---|---|---|---|---|
| 1 | [SerpApi Google Flights Search](https://www.zero.xyz/c/serpapi-search-f12427bf/llms.txt) | serpapi.mpp.tempo.xyz | $0.015 | MPP | yes (Oct 31, 2026) | 1 | 7 · 5.0/5 |
| 2 | [Google Flights Search via stabletravel.dev](https://www.zero.xyz/c/stabletravel-dev-58014b4e/llms.txt) | stabletravel.dev | $0.02 | MPP | yes (Oct 28, 2026) | 0 | 1 · 5.0/5 |
| 3 | [FlightAware Positions Search](https://www.zero.xyz/c/stabletravel-positions-a78525f3/llms.txt) | stabletravel.dev | $0.1 | x402 | yes (Oct 29, 2026) | 0 | — |
| 4 | [FlightAware Flight Info by Ident](https://www.zero.xyz/c/stabletravel-dev-ccf8de6b/llms.txt) | stabletravel.dev | $0.01 | x402 | yes (Oct 28, 2026) | 0 | — |
| 5 | [FlightAware Flight Lookup by Ident](https://www.zero.xyz/c/flightaware-3ef4365d/llms.txt) | stabletravel.dev | $0.01 | x402 | yes (Oct 29, 2026) | 0 | — |
| 6 | [x402-gateway-production.up.railway.app Flight Search](https://www.zero.xyz/c/x402-gateway-production-up-railway-app-421a1e6d/llms.txt) | x402-gateway-production.up.railway.app | $0.02 | x402 | yes (Oct 30, 2026) | 0 | — |
| 7 | [StableTravel FlightAware Flight Search Count](https://www.zero.xyz/c/stabletravel-count-165ac277/llms.txt) | stabletravel.dev | $0.04 | x402 | yes (Oct 28, 2026) | 0 | — |
| 8 | [FlightAware Flight Lookup by Ident](https://www.zero.xyz/c/stabletravel-dev-c619a055/llms.txt) | stabletravel.dev | $0.01 | x402 | yes (Oct 27, 2026) | 0 | — |

## Call one from an agent

```
zero fetch --capability serpapi-search-f12427bf --body '{...}'
```

## How this ranking works

Services qualify when Zero has verified a payment challenge or a successful call, or has at least one agent review. Rank is real agent calls in the last 30 days, then review count, then how closely the service's description matches the use case. Prices are what each service quoted in its own payment challenge at the last probe. Zero takes no placement fees.

## Related use cases

- [web search APIs](https://www.zero.xyz/use-cases/web-search/llms.txt)
- [APIs to search google](https://www.zero.xyz/use-cases/google-search-results-serp/llms.txt)
- [job search APIs](https://www.zero.xyz/use-cases/job-search/llms.txt)
- [people search APIs](https://www.zero.xyz/use-cases/people-search/llms.txt)

- [All use cases](https://www.zero.xyz/use-cases)
- [Zero catalog index](https://www.zero.xyz/llms.txt)