Do different API keys associated on the same usage plan share the same quota limit too?

Do different API keys associated on the same usage plan share the same quota limit too?

Scenario:

• Usage Plan 1 has quota of 1 million requests per month.
• API Key #1 is associated to Usage Plan 1
• API Key #2 is also associated to Usage Plan 1

When API Key #1 consumes 1 million requests in a month, does this mean requests with API Key #2 will all be throttled?

Usage plan is calculated per API key. From the documentation: "Throttling and quota limits apply to requests for individual API keys that are aggregated across all API stages within a usage plan".

You can read more about usage plans in the official documentation