Docs

TruePx documentation

Everything TruePx can do, explained with real screenshots: the dock on the page, each side panel tab, every SEO and Audit check, and how to connect an AI agent.

TruePx is a free Chrome extension for designers, developers, SEO people and anyone who checks websites. You turn it on in a tab, and it adds a dock of tools to that page and a side panel with four tabs. It sends nothing to us, and nothing to an outside service unless you click one of the two checks that say so.

Start here#

New to TruePx? Getting started covers installing it, turning it on, every dock button, the side panel and all keyboard shortcuts in one page.

• Getting startedInstall, turn it on, the dock, the side panel and every keyboard shortcut.
• Troubleshooting & FAQWhen TruePx can’t run on a page, a check can’t finish, or something looks wrong.

Tools on the page#

These work directly on the website, from the dock at the bottom of the screen.

• Measure & layoutSizes, padding, margins and distances; rulers, a column grid, breakpoint lines and X-Ray outlines.
• Inspect & captureThe floating inspector card, find by CSS selector, the color picker and element screenshots.
• Edit the pageChange CSS rules, text and HTML live, see every change as a diff, and undo it.
• Responsive previewThe page at phone, tablet and desktop sizes side by side, with 23 device sizes.
• Design QAColor-blindness simulation, a design mockup laid over the page, and pinned notes.

The side panel#

The side panel opens beside the page and has four tabs. Each has its own page here, with every section explained.

• Element tabEverything about the element you click: box model, CSS (computed, source, Tailwind), colors, fonts, effects and contrast issues.
• Page tabThe whole page: weight by file type, color palette, type styles, downloadable images and SVGs, technologies and pins.
• SEO tabSearch preview, SEO issues, broken links, headings, structured data, language versions and share previews.
• Audit tabAccessibility, launch and privacy, performance, content and layout checks, with how to fix each one.

More#

• AI agents (MCP)Let Claude Code, Cursor or another agent measure, inspect and edit the page through 61 tools.
• Settings & privacyThe settings page, the permissions TruePx asks for, and what is stored or sent.
• ChangelogWhat changed in each version.

Is everything free?#

Yes. Every tool and check in these docs is free, with no account and no trial. Two optional checks use an outside service and say so before you run them: the grammar check (LanguageTool) and Google’s PageSpeed test. See what TruePx sends.