Do I need load testing for every API endpoint?

Not necessarily.

You usually don’t need full load testing for every single endpoint. Instead, focus your effort where it matters most.

Good candidates for load testing

Prioritize endpoints that are:

• High traffic or user-facing critical paths
• Compute-heavy or database-intensive
• Known bottlenecks or historically slow
• Part of key business flows like login, checkout, search, order creation
• Used in bursts (webhooks, batch jobs, notifications, report generation)

Lower priority / usually less critical

You may not need dedicated load tests for endpoints that are:

• Admin-only or rarely used
• Simple CRUD operations with low traffic
• Thin wrappers around already-tested internal services
• Very stable and non-critical, assuming they share the same infrastructure patterns

Better approach

A practical strategy is:

1. Load test representative endpoints for each usage pattern
   • e.g. one read-heavy, one write-heavy, one expensive endpoint
2. Test shared dependencies
   • database, cache, queues, auth, downstream services
3. Test the system as a whole
   • mix endpoints based on expected production traffic
4. Add tests for risky changes
   • new endpoints, major code paths, schema changes, or scaling-sensitive logic

Rule of thumb

If an endpoint:

• can affect many users,
• touches expensive resources,
• or has unknown performance characteristics,

then it’s worth load testing.

If you want, I can help you build a prioritization matrix for your API endpoints so you can decide which ones need load testing and at what depth.