React Developer Tools
Developer ToolsInspect React component trees, props and state.
Watch analytics, GTM and consent events in real-time. 600+ platforms, optional AI features, all in Chrome DevTools.
See every tracking event on your site in real-time - one DevTools panel replacing a stack of vendor-specific debuggers. WHAT'S NEW IN VERSION 1.5.0 ▪️You choose when Event Watcher is active: only while the panel is open, or everywhere except selected sites, or everywhere as today (the default). You can now decide. The current site can be skipped in one click, and the toolbar icon greys out while a page is not being watched. Set it in Settings under Detection scope. ▪️The side panel now has deeper event info. Open any entry to see exactly what was sent, with one button to copy it, and every tool in the list opens to a plain-language description of what it is and why it was detected. ▪️AI features now ask for a level instead of a model name: pick Fast, Balanced or Capable and the extension follows your provider's current model at that level. Existing setups carry over, and the settings are simpler: cost estimates and the automatic-actions toggle are gone. ▪️Improved container intercept scoping: choose whether a rule lasts for the current DevTools session (the default), only while DevTools is open, or always. Rules apply on the site you created them on. ▪️Better performance on sites that push constantly to the dataLayer, such as single-page apps. Sites with a strict content security policy now capture like any other. ▪️Past the 600-tools marker: 19 newly supported tools across ad tech, analytics, A/B testing, marketing automation and widgets, plus 32 existing tools, consent platforms included, extended to the regional addresses they are served from. ▪️Multi-product analytics suites now show each product (session replay, feature flags, surveys) as its own tool. WHAT IT DOES Event Watcher captures tracking activity as it happens and shows you what each tool sent, why it fired, and whether it was allowed to: ▪️Network requests to analytics, advertising, and marketing endpoints ▪️DataLayer pushes across multiple implementations ▪️Tracking script loads, with the full initiator chain showing how each script was loaded ▪️Page navigation (History API, popstate, hash changes) 600+ platforms are detected across analytics, tag managers, advertising, CDPs, consent management, session replay, ad tech, A/B testing, and marketing automation. Each one is shown with its official icon, brand color, and category badge. TWO WAYS IN The DevTools panel is where the debugging happens. Open DevTools on any page and Event Watcher becomes a workbench: the live event stream, parsed payloads, the consent timeline, filters, script dependencies, and every export. When you need to know exactly what a tag sent and why, this is the view. The side panel is the quick first look. One click on the toolbar icon lists every tool running on the current page, what each one is, and what it sent, without opening DevTools. It is the fastest way to answer "what is on this site?" and a natural starting point before you dig in with the DevTools panel. INSPECT ANY EVENT Click an event for parsed parameters in readable tables, custom data, e-commerce items, consent signals, and the raw request. 30+ platforms have dedicated parsers that turn raw payloads into structured, labeled sections. Every tool opens to a plain-language description of what it is and why it was detected. Cookies show whether they were set by the response or sent with the request. Script loads show the chain of scripts that led to them. CONSENT TRACKING ▪️Detects 40+ consent management platforms ▪️Reads consent state from cookies, browser APIs, and dataLayer events ▪️Tracks consent mode across major analytics tags ▪️Shows a full consent timeline: defaults, CMP load, user choice, updates ▪️Highlights potential issues such as tracking before consent or after denial BUILT FOR AI WORKFLOWS ▪️Copy for AI: one click turns the captured session into a compact, AI-ready snapshot you can paste into any assistant to ask "what is wrong with this tracking?" ▪️Built-in AI, bring your own key: explain any event, identify unknown tracking calls, or chat with the whole captured session. Pick Fast, Balanced, or Capable and the extension follows your provider's current model at that level ▪️Nothing is sent to an AI provider unless you set one up and ask FILTER AND FIND Filter by tool, category, script, consent state, and user interaction. Filters combine, and you can save combinations as presets. Keyword search narrows the stream to what you are looking for. VIEWS The same captured session can be looked at in five ways. Switch views to match the question you are asking, from "what fired just now" to "what is this site's whole stack". ▪️ Stream (chronological) ▪️ Grouped (by Tool, Page, Event Name, Consent Category, Datalayer, Endpoint, Cookie, or Identity) ▪️ Script (dependency tree of every tracking script on the page) ▪️ Stack (the site's martech stack at the tool level) ▪️ Pinned (a per-domain parking spot for events that survives Clear and reloads) EXPORT Copy any event, a selection, or the whole session as a readable table, JSON, or the AI-ready snapshot above. Copy the full dataLayer or individual pushes as JSON. Export the Stack view as a Markdown tree, a Mermaid diagram, an SVG, or JSON for diagramming tools. TAG MANAGER TOOLS Container intelligence (versions, tag/variable/trigger counts, dependencies) and container actions to block, swap, or preview a container, with rules scoped to the current DevTools session, to DevTools being open, or always. CUSTOMIZABLE Configurable defaults, custom tracking endpoints for internal or niche platforms, detection scope (only while the panel is open, everywhere except selected sites, or everywhere), resizable panels, keyboard navigation, and dark mode that follows your DevTools theme. WHO IT'S FOR Web developers, a
Event Watcher is free. There is no paid tier to consider.
Inspect React component trees, props and state.
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Simple yet powerful Cookie Editor that allow you to quickly create, edit and delete cookies without leaving your tab.
Yes, Event Watcher is free to use.
Event Watcher is published by eventwatcher.dev. As with any extension, review the permissions it requests before installing and remove it if you stop using it.
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