Install JavaScript Snippet
Add the SEO Core script tag to your site, verify the installation, and configure client-side delivery for active SEO deployments.
What it does
The JavaScript snippet is a lightweight loader that runs when a visitor opens any page on your site. It checks whether there are active deployments for that specific URL, then applies them instantly — updating the title, meta description, headings, content, schema markup, or canonical tag before the visitor notices anything.
Instant activation
Changes you make in the dashboard appear on your live site within seconds — no FTP, no CMS login, no waiting for a developer.
URL-specific targeting
Deployments only apply to the exact URLs you configured. Other pages on your site are untouched.
Version history
Every deployment is versioned. You can enable, disable, or roll back to any previous version at any time from the dashboard.
Works everywhere
Compatible with WordPress, Webflow, Shopify, Wix, custom HTML sites, and any CMS or framework that serves HTML pages.
Requirements
- Access to your site's HTML source or a tag manager (Google Tag Manager, etc.).
- A SEO Core project with a verified domain.
- JavaScript must be enabled in the visitor's browser — this method applies changes client-side.
Note
If your site is server-rendered and you need changes to appear in the raw HTML for search engine crawlers — before JavaScript executes — consider the WordPress Plugin or Node.js Package instead.
Installation
- 1
Open your project in the dashboard
Go to Projects and find the project that matches the website you want to add the script to.
Each project has its own unique script tag — make sure you use the tag for the correct project.
- 2
Copy the script tag
Click Deploy Script on the project card. In the modal that opens, select the Manual tab.
Click the copy button next to the script tag to copy it to your clipboard.
- 3
Paste into your site's <head> element
Open your site's HTML source, theme editor, or CMS template and paste the script tag inside the <head> element on every page you want deployments to cover.
Place it as early in the <head> as possible — before other scripts — so it loads at the highest priority.
Tip
In most CMS platforms, there's a dedicated "Custom code" or "Header injection" section where you can paste the tag once and have it appear on all pages automatically.
- 4
Publish your site
Save and publish your changes through your CMS or site builder. The script tag will now load on every page it was added to.
- 5
Verify installation
Return to the Deploy Script modal in your dashboard and click Verify installation.
SEO Core will visit your site and confirm the script is present. Once verified, the project status will show Script active.
Tip
Verification may take up to a minute if your site has caching. If it fails, try clearing your site cache and verifying again.
Installing via Google Tag Manager
If you use Google Tag Manager and don't have direct access to your site's HTML, you can deploy the script through GTM instead.
- 1
Create a new tag in GTM
In your GTM workspace, click Tags → New. Choose Custom HTML as the tag type.
- 2
Paste the script tag
Copy your script tag from the Deploy Script → GTM tab in your dashboard and paste it into the HTML field.
- 3
Set the trigger to All Pages
Under Triggering, select or create an All Pages trigger so the script loads on every page of your site.
- 4
Save and publish your container
Click Save, then submit and publish the container version. The script will now load on your live site via GTM.
Note
GTM fires after the initial page render, so very fast page loads may briefly show original content before deployments apply. For changes to metadata like title and description, this has no visible impact on users.
What gets changed and how
When you activate a deployment in the dashboard for a specific URL, the script applies it to every visitor of that page automatically:
- Title tags — the browser tab title and search result headline.
- Meta descriptions — the text snippet shown in search results.
- Headings — H1 through H6 tags on the page body.
- On-page content — specific paragraphs or content blocks you've targeted.
- Canonical tags — tells search engines which version of a URL is preferred.
- Schema markup — structured data (JSON-LD) added to the page head.
Tip
Deployments target specific URLs. If you need to change multiple pages, create a separate deployment for each URL from the Crawler or directly in the Deployments dashboard.
Pausing or removing deployments
Pausing a single deployment
Go to SEO Deployments in the dashboard. Find the deployment and toggle it off. The change is live within seconds — the original content is restored for that element.
Pausing all deployments for a URL
In the SEO Deployments view, select a URL and click Pause all to disable every active deployment on that page at once.
Removing the script entirely
Remove the script tag from your site's <head> element (or delete the GTM tag). No deployments will apply — your original content is served as-is.