Requests Per Second Calculator – API and Web Throughput

Calculate required RPS from daily traffic and peak hour patterns.

About This Calculator

Calculate required RPS from daily traffic and peak hour patterns. Use the calculator above for instant results.

Worked Examples

Example 1: 1M requests/day, 3× peak

  • Avg: 11.6 RPS | Peak: 34.7 RPS | Very manageable

Answer: ~35 RPS peak

Example 2: 100M requests/day, 5× peak

  • Avg: 1,157 RPS | Peak: 5,787 RPS | Significant scale

Answer: ~5,800 RPS peak

Example 3: 1B requests/day, 10× peak

  • Avg: 11,574 RPS | Peak: 115,740 RPS | Web-scale

Answer: ~115,000 RPS peak

Who Uses This Calculator?

💻
API Engineers

Size API gateway and backends.

📊
Architects

Capacity planning for services.

🔧
DevOps

Load testing targets.

💾
Product Managers

Understand scale requirements.

Common Mistakes to Avoid

❌ Design for peak, not average

Average traffic is 5-20× lower than peak. Never size infrastructure for average — you'll be down during your most important moments.

❌ 80/20 rule for traffic

80% of daily traffic often occurs in 20% of the day. Peak hour can be 5× the daily average per hour.

Frequently Asked Questions

Peak hour patterns?

Traffic peaks on weekday mornings (10am-12pm) for B2B. B2C peaks evenings (8-10pm). Plan for 3-10× average depending on business type.

How many servers for X RPS?

Depends on application. Simple API: 10,000+ RPS per server. Database-heavy: 100-500 RPS. Load test to measure your actual capacity.

RPS to concurrent users?

Use Little's Law: Concurrent = RPS × response_time. 100 RPS at 200ms response = 20 concurrent connections.