Rate Limits

Your plan sets a monthly request quota and a per-second rate limit; exceeding either returns 429. This page documents plan tiers, the per-second limits, the response headers that expose limits, overage pricing, webhook slot limits, and the Historical ADS-B path tiers that control retention windows.

Quota is enforced in different places on the two channels —

For retry behaviour on 429, see Error Handling → Retry rules. For subscribing or applying for a trial, see Getting Started.

Plans

The FREE Trial is not self-serve — apply at skylinkapi.com/apply. Paid plans are available at our checkout or on the RapidAPI listing. Prices and quotas are the same on both channels; Pro overage differs (see the table for your channel). Compare plans at skylinkapi.com/pricing.

Upgrade, cancel or check usage from your Polar customer portal.

All prices are in USD and exclude VAT and sales tax.

Legacy plans (Ultra and Mega)

Ultra and Mega are no longer sold to new subscribers. Existing subscribers keep their plan, price and limits:

Per-request lookback for Historical ADS-B (archived aircraft position data going back up to 365 days) is enforced by the URL path prefix, not the plan name alone. Use /ultra/history/... for windows up to 90 days and /mega/history/... for up to 365 days (Ultra and Mega only). See Historical ADS-B path tiers below.

Per-second rate limits

Every plan also has a per-second limit. The rate is the sustained number of requests per second; the burst is how many extra requests can arrive at once above that rate before further requests are rejected with 429.

These limits apply to every account, including customers who subscribed before the October 2026 plan change. Existing subscribers keep the price they signed up at; the rate limits are not grandfathered. If you fan out requests in parallel — batch jobs, map tiles, agent tool calls — throttle them client-side to stay under your plan's rate, and treat 429 as a signal to back off.

Need a higher sustained rate? Contact us about Business and Enterprise limits.

Quota headers

Every successful response includes these headers:

These headers report the anti-abuse ceiling, not your monthly plan quota. The ceiling is a hard per-day limit set well above normal usage, there to bound the damage from a compromised or runaway key. Do not use these headers to work out remaining paid quota or your bill — check your Polar customer portal for usage against your plan.

Requests that reach the API and authenticate count toward your allowance, including ones that error because of your input (for example 404 or 422). Requests rejected for a missing or invalid key are not counted.

429 — Rate limit exceeded

When the limit is hit you get:

{ "message": "Too many requests" }

This happens when you exhaust your monthly quota or exceed your plan's per-second rate limit. Back off exponentially and retry. See Error Handling → Retry rules for the full retry table and a Python helper.

Historical ADS-B path tiers

Historical ADS-B endpoints use URL path prefixes that map to retention windows — these prefixes are not RapidAPI plan names:

Ultra and Mega subscribers may call either prefix. Use /ultra/history/... for recent windows (≤90 days) and /mega/history/... when you need longer lookback or higher per-request limits. Pro subscribers are limited to /ultra/history/... only.

Important: Choosing the wrong prefix for your plan or date range returns gateway 401/403 or validation 422 — not a quota 429. Plan-gate errors are documented on the Historical ADS-B hub.

See Historical ADS-B for endpoint details and integration examples.