Paste a 5 kb snippet into your WordPress header and launch your first A/B test in under 15 minutes. No heavy plugin, no render-blocking scripts, no broken Core Web Vitals.
Most WordPress A/B testing plugins are heavy, clutter your backend and slow down your site. Testio lives outside WordPress: the only artifact touching your site is a 5 kb snippet.
Nothing to add to wp-content/plugins. Testio installs by pasting a script into your
header with any script-injection plugin (WPCode, Insert Headers and Footers) or directly in your
theme. Less weight, fewer conflicts, smaller attack surface.
It doesn't matter if you run Astra, GeneratePress, Kadence, Divi, Avada, Blocksy or a custom theme. The visual editor operates on the rendered page, so it doesn't care how your site is built under the hood.
Test headlines, images, prices, add-to-cart buttons, checkout layouts and form fields. Set purchase as your conversion goal and see the real impact on revenue.
The snippet works identically in all three. Pick whichever method feels easiest for you.
<!-- Paste inside <head> --> <script async src="https://testioapp.com/snippet/testio.js" data-api-key="YOUR_API_KEY_HERE" ></script>
Step by step with WPCode: go to Code Snippets → + Add New → Add Your Custom Code (New Snippet). Choose "HTML Snippet", paste the code above, and under Insertion pick "Site Wide Header". Save and activate. Done — the snippet now loads on every page of your WordPress site.
An honest side-by-side of the main A/B testing options for WordPress.
| Feature | Nelio A/B Testing | Thrive Optimize | Split Hero | Testio |
|---|---|---|---|---|
| Integration type | Heavy WP plugin | WP plugin + Thrive Suite | WP plugin | 5 kb snippet |
| Entry price | From €29/mo | $99/yr (Suite $299/yr) | $79/mo | $9/mo |
| Free trial | Limited version | 30-day guarantee | 14 days | 3 days free |
| Visual editor (no-code) | ✓ | ✓ (Thrive landing pages only) | ✓ | ✓ any page |
| Performance impact | High (PHP on every request) | Medium | Medium | Low (anti-flicker <100 ms) |
| Runs outside WordPress | ✗ | ✗ | ✗ | ✓ (cross-platform) |
| WooCommerce compatible | ✓ | Limited | ✓ | ✓ |
| Spanish UI | ✓ | ✗ | ✗ | ✓ |
| Statistical engine | Bayesian | Basic | Bayesian | Bayesian + Z-test |
| Advanced targeting | Limited | Limited | Medium | Device, country, source, language |
No imports, no proprietary plugins in your WordPress. Set up once and start testing today.
Sign up in seconds with your email. Your 3-day trial starts immediately — we don't charge until the trial ends and you can cancel with one click.
Copy one line and paste it into your WordPress header via WPCode, Insert Headers and Footers, or your child theme. Takes less than 3 minutes.
Open any page of your WordPress in the Testio visual editor. Tweak headlines, CTAs, images, colors. Define your conversion goal.
Watch results in real time. In days you'll have a winner with real statistical significance, and you can ship the change to your WordPress for good.
Real A/B tests you can launch today with Testio on your WordPress or WooCommerce site.
Headlines, subheadings, hero images, primary CTA, order of sections.
Product name, images, short description, displayed price, "Add to cart" button.
Visible fields, trust badges, order summary, purchase button copy.
Field count, order, button copy, microcopy.
Headlines, featured image, capture blocks (newsletter, related posts).
Plan order, highlighted plan, benefit copy, displayed prices.
Nelio starts at €29/mo. Thrive Optimize requires buying their suite. Testio starts at $9/mo — no suite, no upsell, no bundles.
All plans include the visual editor, statistical analysis, unlimited variants and support. Full comparison →
Everything you need to know before trying Testio on your WordPress.
Not necessarily. Testio runs from a lightweight snippet (~5 kb) that you can add to your header using any script-injection plugin (WPCode, Insert Headers and Footers, Site Kit, etc.) or directly in your theme. There is no proprietary plugin that bloats your site.
Yes. Testio's visual editor operates on the final rendered page, so it doesn't matter whether you use Elementor, Divi, Beaver Builder, Gutenberg, Oxygen or a classic theme. You can run tests on landing pages, WooCommerce product pages, blog posts, forms, etc.
The snippet is around 5 kb gzipped and uses anti-flicker technology under 100 ms, so the impact on LCP and CLS is minimal. It loads asynchronously and doesn't block rendering. It's lighter than most A/B testing plugins available on the WordPress repository.
Yes. Testio works on any WooCommerce store: test headlines, add-to-cart buttons, images, colors, displayed prices, product descriptions, checkout fields, etc. Set purchase or any other event as your conversion goal.
Works fine. The snippet is served from our infrastructure and variant assignment happens client-side, so the cached HTML doesn't change: every visitor receives the same HTML and the snippet decides which variant to show in the browser. No cache exclusions needed.
Yes. We store data on EU-based infrastructure, never sell or share it, and you can export or delete everything from your account at any time. We don't rely on third-party cookies for A/B tracking.
3-day free trial · Cancel anytime · From $9/mo after the trial
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