Latency, throughput, and page speed calculators. Browse our free performance tools below — all calculators are instant, accurate, and require no sign-up.
Apdex Score Calculator — Calculate your Application Performance Index (Apdex) score from satisfied, tolerating, and frustrated user counts with a custom threshold.
Bandwidth Calculator — Calculate required bandwidth from file size, concurrent transfers, and time window. Plan network capacity for file-heavy applications.
Cache Hit Ratio Calculator — Calculate cache hit ratio from hits and misses. Measure caching efficiency and estimate the performance benefit of your cache layer.
CDN Hit Ratio Calculator — Calculate CDN cache hit ratio and origin offload percentage. Measure how effectively your CDN serves content from edge locations.
Concurrent Users Calculator — Estimate concurrent active users from session data. Calculate simultaneous users from active sessions, duration, and time period.
Connection Pool Sizing Calculator — Calculate optimal database connection pool size from concurrent requests, query time, and overhead. Prevent pool exhaustion and optimize resources.
Core Web Vitals Calculator — Check your Core Web Vitals scores against Google thresholds. Evaluate LCP, FID/INP, and CLS values for good, needs improvement, or poor.
Database Query Optimization Calculator — Calculate query optimization improvement percentage and annual time savings. Measure the impact of database query tuning on performance.
Download & Upload Time Calculator — Calculate file download and upload time from file size, bandwidth, and protocol overhead. Estimate transfer times for any connection speed.
GC Pause Impact Calculator — Calculate garbage collection overhead and throughput impact. Estimate the percentage of runtime spent in GC and effective application throughput.
Latency Percentiles Calculator — Calculate latency percentiles (p50, p90, p95, p99) from response time samples. Understand your service latency distribution for SLOs.
Lighthouse Score Estimator — Estimate your Lighthouse performance score from FCP, SI, LCP, TBT, and CLS metrics using official scoring weights for version 10+.
Load Test Sizing Calculator — Calculate target virtual users and ramp-up plans for load tests. Size your performance tests from peak concurrent users with safety factors.
Page Load Time Estimator — Estimate total page load time from page weight, bandwidth, DNS, TLS, TTFB, and render time. Plan optimization targets for faster pages.
Page Response Time Impact Calculator — Calculate how page load latency affects revenue and conversions. Estimate revenue loss per second of added delay for your website.
Page Weight Calculator — Calculate total page weight from HTML, CSS, JS, images, fonts, media, and third-party resources. Optimize your page size for faster loads.
Requests Per Second Calculator — Calculate average and peak requests per second from total requests and time period. Estimate peak RPS with configurable multipliers.
Throughput Capacity Calculator — Calculate max throughput using Little's Law from average response time and concurrent workers. Plan server capacity for peak loads.
Thread Pool Sizing Calculator — Calculate optimal thread pool size for CPU-bound and I/O-bound workloads. Use the cores+1 and wait/service ratio formulas for accurate sizing.