Most traditional split testing and A/B testing tools work well on landing pages.

They optimize things like:

• Headlines
• Buttons
• Hero images
• Pricing blocks

But the moment a user clicks Buy Now and enters checkout, these tools silently stop working.

This is not a coincidence.

It is a structural limitation of how legacy experimentation tools were designed.

CBSplit exists specifically because of this gap.

In modern affiliate and SaaS funnels, checkout is often:

• Hosted on third-party platforms
• Embedded via iframe
• Redirected to a payment processor domain

Common examples include:

• Sticky.io
• CheckoutChamp
• Digistore24
• ThriveCart
• Custom PSP-hosted flows

Traditional split testing tools rely on:

• JavaScript injected on your own domain
• DOM-level manipulation
• Page-level variation assignment

Once the user leaves your domain, that control is lost.

CBSplit was designed with the assumption that checkout is external, not internal.

Landing pages are mostly stateless.

You can reload them without consequences.

Checkout pages are different. They are:

• Session-bound
• Tokenized
• Order-state dependent

Small changes can:

• Break order attribution
• Invalidate payment tokens
• Trigger fraud protection rules

Most testing tools intentionally avoid checkout to reduce operational and legal risk.

CBSplit operates around checkout state, instead of injecting scripts blindly into it.

Checkout pages operate under strict controls such as:

• PCI compliance
• Fraud detection systems
• Risk scoring engines

Injecting uncontrolled third-party scripts can:

• Increase compliance risk
• Violate processor terms
• Raise fraud flags

Because of this, checkout providers often restrict:

• Script execution
• DOM mutation
• External tracking tools

CBSplit does not try to bypass these restrictions.

Instead, it routes logic before checkout and after checkout where it is safe and reliable.

Most A/B testing tools are designed to optimize:

• Click-through rate
• Button engagement
• Page-level conversions

They stop measuring the moment the user leaves the page.

Critical checkout outcomes such as:

• Payment declines
• Retry success rates
• Upsell acceptance
• Subscription retention

Remain invisible to them.

CBSplit treats checkout as a revenue engine, not a black box.

Standard split testing tools rely on:

• Browser cookies
• Client-side identifiers
• Session continuity

Checkout flows often involve:

• Cross-domain redirects
• Server-to-server callbacks
• Asynchronous payment confirmations

Attribution breaks at this point.

CBSplit uses:

• Server-side event stitching
• Order-level identifiers
• Postback-driven attribution

This replaces browser guesses with transaction truth.

Proper checkout testing involves changing things like:

• Offer structure
• Billing model
• Retry and decline logic
• Subscription terms

This is not a CSS or UI problem.

It is a systems-level problem.

CBSplit operates at the system layer, not as a page decorator.

Traditional split testing tools stop at checkout because:

• They lack domain control
• They avoid compliance risk
• They cannot safely handle state
• They optimize surface metrics

CBSplit starts at checkout because:

• That is where revenue is decided
• That is where failures happen
• That is where optimization has real impact

Traditional split testing tools were built for marketing pages.

They were not built for:

• Payment systems
• Retry logic
• Subscription economics
• True revenue attribution

CBSplit exists to operate precisely where other tools deliberately stop.

At checkout.