iPerf2 vs LibreSpeed

iPerf2 measures network traffic performance, including throughput, latency, link capacity, and responsiveness. Testing uses a client to send traffic to a server. It can generate TCP and UDP traffic in one-way, bidirectional, full-duplex, and simultaneous multi-stream configurations. Measurements include one-way delay, round-trip time, jitter, packet loss, and throughput. It supports IPv4, IPv6, and multicast, including source-specific multicast joins, and reports can include enhanced metrics or use CSV format. The project manual describes an Android client with live meters for throughput, latency, and congestion signals. The manual also describes permit-key HMAC authentication using a timestamped HMAC-SHA256 value, with replay limited by a configurable time window. Its Professional feature set includes server access gating and remotely enabled server-side latency histograms. Measurements happen at socket-level reads and writes, so lower-level protocol-header overhead is excluded. iPerf2 and iPerf3 are separate implementations and do not interoperate. It runs on Android, Linux, macOS, and Windows, and can be self-hosted. Both listed editions are free.

LibreSpeed is a lightweight JavaScript speed test that uses XMLHttpRequest and Web Workers to measure download, upload, ping, and jitter. It supports IE11, current Edge, Chrome, Firefox, Safari, and mobile browser versions. Telemetry and result sharing are optional, and an installation with multiple test points can automatically select the point with the lowest ping. A separate stability test reports current, average, minimum, and maximum latency, jitter, failed-request percentage, threshold alerts, and CSV export. It can target a local backend, configured test points, or Google, Cloudflare, and Apple. Deployment uses a web server such as Apache, nginx, or IIS with PHP 5.4 or newer, though other backends are available. Optional result storage supports MariaDB, MySQL, Microsoft SQL Server, PostgreSQL, and SQLite. The project provides an Android client template, a command-line client, and a .NET client library through NuGet. Go and Rust implementations are available; the Node.js implementation is partial and not recommended. LibreSpeed is free and open source, with self-hosting and no paid plans listed.