Run Javascript - Chrome Web Store

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Overview

Run custom Javascript, each time you visit a website

⚡ Run custom JavaScript on any website — automatically, every time you visit. Save your scripts per domain. They execute on page load, every single time. No setup, no config files, no extra tools. Just your code running where you want it. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔧 HOW IT WORKS 1. Visit any website 2. Click the Run JavaScript icon 3. Write or paste your custom JavaScript code 4. Save — your script auto-runs on every future visit to that domain Toggle scripts on/off per site with one click. Scripts persist across browser restarts. ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🎯 WHAT YOU CAN DO ✅ Remove ads, popups, banners, cookie notices, and distracting elements ✅ Inject custom CSS — dark mode, custom themes, font changes, layout fixes ✅ Auto-fill forms, pre-select dropdowns, auto-click buttons ✅ Auto-run scripts on page load without manual intervention ✅ Extract data, scrape content, highlight information on any page ✅ Add features websites are missing — keyboard shortcuts, UI tweaks ✅ Automate repetitive tasks — clicks, form submissions, navigation ✅ Inject custom HTML elements, dashboards, or productivity widgets ✅ Test and prototype frontend code changes on live websites ✅ Debug and inspect page behavior with custom console scripts ✅ Modify DOM elements, rewrite page content, restructure layouts ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 💻 BUILT FOR DEVELOPERS ✅ Ace code editor with full syntax highlighting and auto-indent ✅ jQuery library included (1.12.4, 2.2.4, 3.3.1) — or use vanilla JavaScript ✅ Execute button for instant testing before saving ✅ Scripts stored per hostname using Chrome storage API ✅ One-click enable/disable toggle per domain ✅ Works on all http and https pages ✅ Manifest V3 — secure, fast, modern Chrome extension architecture ✅ Service worker background script — no performance overhead ✅ Sandboxed execution with duplicate run prevention ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 👤 WHO USES THIS → Web developers testing and debugging on production sites → Frontend engineers prototyping UI changes live → QA testers injecting test scripts and automation → Digital marketers running A/B tests and analytics scripts → Power users customizing websites to fit their workflow → Students learning JavaScript with real-world web pages → Automation enthusiasts replacing repetitive manual tasks ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 📝 EXAMPLE SCRIPTS Remove cookie banners: document.querySelector('[class*="cookie"]')?.remove() Force dark mode on any site: document.body.style.cssText = 'background:#1a1a1a!important;color:#eee!important' Auto-expand collapsed content: document.querySelectorAll('[aria-expanded="false"]').forEach(el => el.click()) Hide sidebar navigation: document.querySelector('aside')?.style.display = 'none' ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ 🔒 PRIVACY & SECURITY → No data collection, no tracking, no analytics → No account required — works immediately after install → All scripts stored locally in your browser → Open source and transparent → Manifest V3 security standards → No external network requests ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━ Lightweight. Fast. Private. Just your JavaScript, running where you want it. Install now → click the icon → paste your code → done.

Details

  • Version

    5.1.5

  • Updated

    May 17, 2026

  • Size

    283KiB

  • Languages

  • Developer

  • Non-trader

    This developer has not identified itself as a trader. For consumers in the European Union, please note that consumer rights do not apply to contracts between you and this developer.

Privacy

Manage extensions and learn how they're being used in your organization

The developer has disclosed that it will not collect or use your data. To learn more, see the developer’s privacy policy.

This developer declares that your data is

  • Not being sold to third parties, outside of the approved use cases
  • Not being used or transferred for purposes that are unrelated to the item's core functionality
  • Not being used or transferred to determine creditworthiness or for lending purposes

Support

For help with questions, suggestions, or problems, visit the developer's support site

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