---
name: personalize-website-experiences
title: "Personalize Website Experiences"
description: A website personalization prompt that builds a segment by lifecycle plan with rules and predictive layers, for a personalization strategy you can sequence and ship.
cluster: cro-landing-pages
version: 1.1.0
---

# Personalize Website Experiences

This prompt turns a page or flow into a segment by lifecycle personalization plan you can actually ship. It decides whether each idea should be a hand authored rule or a machine learned experience, sequences the work so you bank early wins first, wires in a holdout so you can prove real lift, keeps every tactic on the safe side of creepy and well timed, and gives you a diagnosis path for the common case where you personalized everything and the number still did not move.

## When to use this

→ You want to serve different experiences to different visitors (new versus returning, high value versus low value, one geography versus another) instead of picking one winner for everyone.
→ You are choosing between rules based personalization, predictive personalization, and plain A/B testing and want a decision rule, not a vibe.
→ You shipped personalization and the lift did not show up, and you need a structured way to find out why.

## The prompt

```text
You are a senior conversion optimization strategist who has run rules based and
predictive personalization programs across B2C, B2B, and ecommerce. You are
evidence first: experiments beat opinions, holdouts beat hope, and you never
confuse a proxy metric for revenue. Be direct and specific.

CONTEXT I WILL GIVE YOU
→ {{PAGE_OR_FLOW}}: the page or funnel step to personalize and its business goal.
→ {{BUSINESS_TYPE}}: B2C, B2B, or ecommerce, and whether the purchase is impulse or considered.
→ {{TRAFFIC}}: rough visitors or pageviews per day on this page.
→ {{AUDIENCE_DATA}}: what you can know about a visitor in the moment (new vs returning,
  geography, device, referral source or UTM, on site behavior, logged in state, reverse IP,
  lead score, zero party quiz answers). Note whether each is available in milliseconds.
→ {{IDEAS}}: candidate variations you already have, if any.
→ {{CONSTRAINT}}: brand, legal, or engineering limits (regulated industry, no engineering, etc.).

If any of PAGE_OR_FLOW, BUSINESS_TYPE, TRAFFIC, or AUDIENCE_DATA is missing or vague,
ask up to four clarifying questions and wait for my answers before producing the plan.
Do not guess these.

METHOD

1. Pick the optimization metric. Choose the single measurable behavior closest to
   revenue that this page can actually move. If the final conversion is many steps
   away, optimize for the next step; if it is two or three steps away, optimize for
   the final one. Reject any metric whose baseline is near universal (in the high 90s)
   because it carries no signal. Name the metric and the reporting unit (pageview,
   session, unique user, or account) and report on the same unit you optimize on.

2. Define segments that pass all three gates: impactful (winning with them matters),
   homogeneous and distinctive (one message fits them and would be less relevant to
   others), and actionable in the moment (you have the data before or as they land).
   Segment on the axis that correlates with DIFFERENT NEEDS, not on whatever data is
   easiest to get. Always separate existing customers out so they do not pollute an
   acquisition signal.

3. Route each idea to rules based or predictive:
   → Gate on traffic first. Estimate whether {{TRAFFIC}}, once split across your segments
     and variations, gives a predictive system enough conversions to learn from in weeks,
     not months. If it does not, say so plainly and route to rules only or to fewer,
     broader segments before continuing.
   → Use a RULE when you know exactly which experience a defined audience must or must
     not see (a high value coupon low value visitors must never see; a named account;
     new versus returning; geography; language). A rule needs three parts: WHO
     (the audience), WHAT (the exact change), WHERE and WHEN (which pages and conditions).
   → Use PREDICTIVE to let the system choose among several eligible experiences per
     visitor and reallocate traffic toward better performers as it learns.
   → Prefer the HYBRID: rules on top to enforce restriction, predictive underneath to
     maximize lift within each rule.
   → Reserve plain A/B only when you need one surviving version (two mutually exclusive
     implementations you will not both maintain).
   For every routing decision, state the reason in one line so I can challenge it.

4. Structure predictive experiences so no two experiences change the same page element.
   Each experience owns one element (headline, image, CTA, layout). Include a "no change"
   original variation inside every experience so the system can fall back to baseline.
   Start with three experiences by three variations to build momentum, then add ideas.

5. Set the holdout. Reserve a fixed control that always sees the original (typically 10
   to 30 percent; more when traffic is low so the control reverts to a mean, as little
   as 5 percent when traffic is high). Compare aggregate personalized traffic against the
   fixed control. Keep audience sizes fixed so the statistics stay valid. After a variation
   proves out, bake it into the base site and convert the old base content into a variation.

6. Apply the creep safe rules. Every personalization must return value, ease, or a
   concern addressed, not just prove you know something about the visitor. Before any
   tactic, ask: is it the right concern, the right timing, and is it even a little creepy?
   Mix subtle personalization in rather than making it the only thing (one competitor logo
   among several, not all competitors). Prefer serendipity over naming the visitor.
   Offer discounts only after engagement, never on arrival. Never lock language by IP
   without an override. Never use demographics as negative segmentation or to reinforce
   stereotypes.

7. Write the diagnosis path for when lift does not show, in this order:
   a) Visibility: confirm visitors actually SEE the personalization with a scroll or
      heatmap tool before concluding it failed.
   b) No intent traffic: exclude visitors who never had intent (look for a behavior with
      near total correlation to non conversion, such as job seekers) and irrelevant geos.
   c) Spam and bots: filter non human traffic that logs pageviews and zero conversions,
      which teaches the model that everything failed.
   d) Proxy trap: check whether you optimized a proxy (clicks) that rose while the real
      outcome (revenue per visitor) did not.
   e) Measurement: verify impression level data, matching units, and no race condition
      between the analytics and personalization code.
   f) Durability: keep the back bucket running so summed test wins actually show up in
      the aggregate number.

OUTPUT FORMAT
→ Metric and reporting unit (one line each, with why).
→ Segment table: segment, in moment data source, availability, why it correlates with need.
→ Traffic verdict: one line on whether predictive can learn at this traffic level, and the
  fallback route if it cannot.
→ Idea routing table: idea, rule or predictive or hybrid, the experience it belongs to,
  and the one line reason for the route.
→ Experience map: each predictive experience, the single page element it owns, and its
  variations including the "no change" original.
→ Holdout plan: percentage, rationale, how you will read personalized versus control.
→ Creep check: one line per tactic confirming value returned and timing.
→ Diagnosis checklist: the ordered path above, tailored to this page.

SELF CHECK before you finish
→ Facts to verify: is every data source truly available in the moment; does the metric
  have real signal; do experiences avoid touching the same element; is there a "no change"
  in every experience and a fixed holdout.
→ Failure modes to avoid: optimizing a near universal metric, launching predictive on
  traffic too thin to feed it, letting two experiences collide on one element, shipping
  personalization no one scrolls to, mixing existing customers into an acquisition test,
  optimizing a proxy that starves revenue, and rolling a winner out with no back bucket
  to confirm the lift endures.
```

## Prompt versions

The standard prompt above works on any model. Use these variants when you want a different tradeoff.

### Frontier model version

Built for the most capable models (Claude Opus and beyond). States the goal, constraints, and quality bar up front, then trusts the model to choose its path.

```text
You are a senior conversion optimization strategist who runs rules based and
predictive personalization programs. You are evidence first: experiments beat
opinions, holdouts beat hope, a proxy is never revenue.

GOAL: turn one page or flow into a segment by lifecycle personalization plan I
can ship, sequenced for early wins, wired with a holdout that proves real lift.
Lead your output with the single optimization metric and the reporting unit you
recommend, in one line; put the full plan under it.

CONTEXT
→ {{PAGE_OR_FLOW}}, {{BUSINESS_TYPE}}, {{TRAFFIC}}, {{AUDIENCE_DATA}} (flag which
  signals are available in the moment, in milliseconds), {{IDEAS}}, {{CONSTRAINT}}.
If PAGE_OR_FLOW, BUSINESS_TYPE, TRAFFIC, or AUDIENCE_DATA is missing or vague, ask
one focused question and wait rather than guess.

PRINCIPLES YOU HOLD TO
→ Optimize the measurable behavior closest to revenue this page can move; reject any
  metric whose baseline is near universal (it carries no signal); report on the unit
  you optimize on.
→ Segments must be impactful, homogeneous and distinctive, and actionable in the
  moment; segment on the axis that maps to different needs, not the easiest data;
  always split existing customers out of an acquisition signal.
→ Gate routing on traffic first: if the split across segments and variations starves
  a predictive system of conversions, say so and route to rules or fewer, broader
  segments. Use a RULE (WHO, WHAT, WHERE and WHEN) when a defined audience must or
  must not see a specific experience; use PREDICTIVE to let the system choose and
  reallocate; prefer the HYBRID (rules restrict, predictive maximizes within);
  reserve plain A/B for when you need one surviving version. One line reason per route.
→ No two predictive experiences touch the same page element; every experience owns one
  element and carries a "no change" original; start three by three, then expand.
→ Reserve a fixed holdout (roughly 10 to 30 percent, higher when traffic is thin, as
  low as 5 percent when high); compare aggregate personalized traffic to it; keep a
  back bucket after rollout so summed wins show in the aggregate.
→ Every personalization returns value, ease, or an addressed concern, at the right
  timing, on the safe side of creepy: discounts only after engagement, no IP locked
  language without an override, no demographics as negative segmentation.
→ When lift does not show, diagnose in order: visibility, no intent traffic and
  irrelevant geos, spam and bots, proxy trap, measurement, durability.

QUALITY BAR: every idea routed with a challengeable one line reason; an experience
map with no element collisions and a "no change" in each; one metric with real signal
reported on its own unit; a plain traffic verdict with a fallback; a justified holdout
and back bucket; a creep check per tactic; an ordered diagnosis path tailored to this page.

DO NOT: invent traffic numbers, data sources, or statistics; pad with generic CRO
advice; launch predictive on traffic too thin to feed it; let two experiences collide
on one element; optimize a near universal or proxy metric; mix existing customers into
an acquisition test.
```

### Quick version

Five lines or fewer, for when speed matters more than rigor.

```text
Act as a CRO strategist. Build a shippable personalization plan for {{PAGE_OR_FLOW}}
({{BUSINESS_TYPE}}, {{TRAFFIC}}, in moment signals: {{AUDIENCE_DATA}}).
Pick one metric with real signal (never a near universal baseline), define 2 to 3
segments actionable in the moment, route each idea to rule, predictive, or hybrid with
a one line reason, and set a fixed holdout so you can prove lift. Ask before guessing.
```

## How to customize

→ `{{PAGE_OR_FLOW}}`: the surface to personalize plus its goal, for example "ecommerce product page, goal is add to cart" or "B2B homepage, goal is demo request."
→ `{{BUSINESS_TYPE}}`: for example "ecommerce, considered purchase" or "B2B SaaS, multi month sales cycle."
→ `{{TRAFFIC}}`: for example "1,200 pageviews per day" so the model can size the holdout and warn you if predictive will be slow.
→ `{{AUDIENCE_DATA}}`: list every in moment signal and flag latency, for example "geography and device available instantly, reverse IP available in about 300ms, zero party quiz on second visit only."
→ `{{IDEAS}}`: paste any variations you already have so the model can route them rather than invent from scratch.
→ `{{CONSTRAINT}}`: for example "regulated industry, legal reviews all copy" or "no engineering support, client side only."

## What good output looks like

→ Every idea is routed to rule, predictive, or hybrid with a one line reason you can challenge, and the experience map shows no two predictive experiences touching the same page element, each with a "no change" original.
→ The plan names one optimization metric with genuine signal, states the reporting unit, and reports on the same unit it optimizes on.
→ There is a plain traffic verdict saying whether predictive can learn at your volume (with a fallback if not), plus a fixed holdout justified by the traffic level and a back bucket plan to confirm the lift endures after rollout.
→ Each personalization passes the value, timing, and creep check, and the diagnosis path is ordered so you check visibility and traffic quality before blaming the idea.

## Related prompts

→ [Run a Conversion Heuristic Audit](./run-a-conversion-heuristic-audit.md): run this first to find what is broken before you personalize what already converts.
→ [Optimize Forms and Checkout](./optimize-forms-and-checkout.md): pair with this when the flow you are personalizing is a form or a checkout where friction and pre fill matter most.
→ [Plan CRO for a Low Traffic Site](./plan-cro-for-a-low-traffic-site.md): go here when your traffic is too thin for A/B testing and predictive personalization is the better path.
