Traditional tools swap content with JavaScript after the page loads — visitors see it flash, and Core Web Vitals suffer. Twofold changes the HTML at the network edge, before the browser ever sees it.
No script tag. No registrar passwords. One DNS record per client site.
No code changes on the client's website. No access to their hosting. No tag managers.
The client adds one CNAME record at their DNS provider. Traffic now flows through the edge network. Nothing changes until a test is switched on — and no passwords ever change hands.
Define the change with simple CSS selectors: swap a headline on #hero-title, recolor .buy-button, remove a banner. Half of visitors see the original, half see the variant — assigned in under a millisecond.
One line on the thank-you page counts conversions. Each visitor counts once. Read views, conversions, and conversion rate per variant, live.
of edge compute per request
locations worldwide, tests run nearest each visitor
scripts added to the client's page
DNS record to go live on a client site
| JS tools (Optimizely, VWO, …) | Twofold | |
|---|---|---|
| Visible flicker on load | Yes — old content flashes | Never |
| Page speed impact | Extra script blocks rendering | None — no script on the page |
| Core Web Vitals | Hurt by layout shifts | Untouched |
| SEO safety | Crawlers can see test content | Crawlers always get the original |
| Works when JS is blocked | No | Yes |
| Setup on client site | Script tag in the template | One DNS record |
Every test comes with a built-in statistical verdict. Twofold tells you when a result is real — and refuses to call a winner while it could still be luck.
4,800 views · 210 conversions
4,750 views · 289 conversions
Variant B converts 39.1% better. This result is statistically significant — safe to act on.
The variant is chosen and applied at the network edge, before the page reaches the browser. There is nothing to flash.
Search engine crawlers always receive the original page. Google never sees test content, so there is no cloaking risk.
If a test config is broken or anything errors, visitors simply get the original page. A test can never take a client's site down.
Each visitor keeps the same version for 30 days, and caching is handled so the browser can never show the wrong one.
A built-in significance test separates real wins from lucky streaks — the tool won't let you report noise to a client.
Your clients, your brand, your invoices. Results come from a simple API you can plug into your own reports.
White-label friendly: run tests for your clients, bill them your way. Launch pricing — locked in for early customers.
No. Their site keeps running exactly where it runs today. They add one DNS record so traffic passes through the edge network. The only optional addition is a one-line snippet on the thank-you page to count conversions.
No. Search engine crawlers are detected and always receive the original, unmodified page. Google never sees variant content, so there is no cloaking risk — safer than JavaScript tools, where crawlers can execute the test script.
The system fails open: if a test config is broken or anything errors, visitors simply get the original page. A test can never take a client's site down.
No. Each visitor is assigned once and keeps the same variant for 30 days via a cookie, and caching is handled so the browser can never show the wrong version.
Replace text or HTML, change styles and attributes, remove elements, or add content — targeted with simple CSS selectors like IDs and classes. Headlines, buttons, prices, banners: the things that move conversion rates.
On Cloudflare's edge network — over 300 locations worldwide. Variant assignment and HTML changes happen in under a millisecond of compute, at the location nearest each visitor.
We're onboarding a small group of CRO and marketing agencies. Early customers keep launch pricing and get hands-on onboarding for their first client test.
Request early accessOpens your email app — tell us your agency name and how many client sites you manage.