@ohmyperf/cli

Real-machine, real-browser web performance measurement CLI. Measures Core Web Vitals (LCP / INP / CLS / TBT / FCP / TTFB) on your hardware, captures cross-origin iframe metrics via CDP OOPIF, and produces self-contained HTML reports + slide decks.

ohmyperf run https://example.com

Install

# one-off
npx -y @ohmyperf/cli run https://example.com

# global
npm install -g @ohmyperf/cli
ohmyperf run https://example.com

Requires Node ≥ 22. Playwright Chromium is downloaded on first run (~150 MB).

Quick start

# Measure 5 runs, output HTML + JSON + deck
ohmyperf run https://shop.example.com

# CI-stable mode: CPU calibration + Fast 4G throttle
ohmyperf run https://shop.example.com --mode=ci-stable --runs=5

# Brand-styled deck for stakeholders
ohmyperf run https://shop.example.com --style=stripe --format=deck

# Diff two runs with Mann-Whitney U significance test
ohmyperf diff baseline/report.json candidate/report.json

Outputs land in ./ohmyperf-output/ by default (configurable via --output-dir).

Commands

| Command | Description | |---|---| | ohmyperf run <url> | Measure a URL. Omit URL in a TTY to launch interactive prompt. | | ohmyperf diff <baseline> <candidate> | Mann-Whitney U significance test between two reports. Exit 1 on regression. | | ohmyperf share <file> | Upload to a share-server with env-secret scrubber + optional password + expiry. | | ohmyperf doctor | Diagnose Node / OS / browser / plugin set; non-zero on broken setup. | | ohmyperf init --ci <provider> | Scaffold CI templates (GitHub Actions / GitLab CI / CircleCI). | | ohmyperf list-plugins | List built-in plugins with version + capabilities. | | ohmyperf list-styles | List the 4 brand styles (calibre / linear-app / stripe / vercel). | | ohmyperf install-browser | Idempotent Playwright Chromium install. |

Use ohmyperf <command> --help for flags.

What you get

• Real machine, real Chromium — not synthetic cloud, not Lighthouse's simulated lantern model.
• OOPIF coverage ~99% — Target.setAutoAttach({ flatten: true }) gets a real CDPSession per cross-origin iframe (Stripe Elements, Intercom, YouTube embed, ad iframes…).
• Mann-Whitney U significance — N runs (default 5), non-parametric diff with per-metric noise floors. Distinguishes real regressions from variance.
• CPU calibration — --mode=ci-stable runs a JS benchmark before measurement, normalizes to a reference hardware profile (mid-range-2024-laptop, 250 ms). Cross-machine CI comparisons stop lying.
• Self-contained HTML + deck artifacts — 1 file, zero CDN, zero tracking. Open in 5 years, still works.
• Brand-aware reporting — --style=calibre|linear-app|stripe|vercel. WCAG-AA gate enforced in CI.

Why ohmyperf vs Lighthouse / DevTools / WebPageTest / SpeedCurve

OhMyPerf is the only tool that combines:

1. Local lab measurement on your hardware
2. A portable, single-file shareable artifact
3. An MCP server surface (@ohmyperf/mcp-server) for AI coding agents

See the project README for the full positioning matrix.

AI agent integration

Use the companion @ohmyperf/mcp-server to expose measurement, regression analysis, and budget enforcement as MCP tools (Claude, Cursor, OpenCode, Copilot).

License

Apache-2.0 — see LICENSE and NOTICE.

Links

• GitHub: https://github.com/hoainho/ohmyperf
• MCP server: @ohmyperf/mcp-server
• Issues: https://github.com/hoainho/ohmyperf/issues