API Rate Limiting Calculator
Optimal rate limiting configuration made simple
API Endpoint
Rate Limiting Configuration
Recommended base RPS: 10
Token Bucket allows burst traffic up to the bucket capacity, then refills at the specified rate.
API Rate Limiting Calculator - Test & Optimize Your API Performance
Professional API rate limiting calculator with real-time testing, multiple algorithms (Token Bucket, Sliding Window, Fixed Window), and comprehensive performance analysis. Optimize your API's rate limiting strategy with detailed metrics and recommendations.
Features
- Multiple rate limiting algorithms (Token Bucket, Sliding Window, Fixed Window)
- Real-time API testing and simulation
- Interactive configuration calculator
- Performance metrics and analysis
- Traffic pattern simulation
- Rate limiting strategy comparison
- Burst capacity optimization
- Response time analysis
How to use
- Enter your API endpoint URL
- Select a rate limiting strategy (Token Bucket, Sliding Window, or Fixed Window)
- Configure requests per minute, burst capacity, and window settings
- Set test duration and concurrent request parameters
- Click 'Start Test' to begin the rate limiting simulation
- Monitor the test progress and view detailed results
- Analyze performance metrics and rate limiting effectiveness
Tips & Best Practices
- Token bucket suits bursty workloads — pick a bucket size that absorbs your spike, refill at your steady-state rate.
- Sliding window is fairer to clients than fixed window because it doesn't allow doubled traffic at the boundary.
- Fixed window is the simplest to implement and reason about; expect uneven request distribution at boundaries.
- The "test" mode is a Monte-Carlo simulation using random arrival times — it does not contact your real API.
- Use the simulation to compare strategies side-by-side before wiring the chosen one into your gateway or middleware.
FAQ
Which rate limiting algorithm should I choose?
Token Bucket is best for handling burst traffic, Sliding Window provides precise control, and Fixed Window is simplest to implement but can allow bursts at window boundaries.
How do I handle traffic spikes with rate limiting?
Configure burst capacity to allow temporary spikes above your base rate limit. The calculator analyzes your traffic patterns to suggest optimal burst settings.
What does the test simulation do?
The simulation sends requests to your API endpoint according to the configured rate limiting strategy and measures response times, success rates, and throughput.
How accurate are the performance calculations?
Calculations are based on real API calls to your endpoint, providing accurate response times and rate limiting behavior analysis. The tool is engineered to handle both small and large inputs efficiently, leveraging modern browser capabilities for optimal performance.
Can I test different rate limiting strategies?
Yes, you can compare Token Bucket, Sliding Window, and Fixed Window strategies side-by-side to see which works best for your API.
What metrics should I focus on?
Pay attention to throughput (RPS), error rate, and response times. A good rate limiting configuration should maintain high throughput while keeping error rates low.
How do I optimize for my specific use case?
Adjust burst capacity for traffic spikes, window size for precision, and test duration to match your typical usage patterns.
What if my API doesn't have rate limiting?
The tool will show you how your API would behave with different rate limiting strategies, helping you plan implementation. The tool is engineered to handle both small and large inputs efficiently, leveraging modern browser capabilities for optimal performance.