Primary Funnel Conversion %, PostHog

Primary Funnel Conversion % for PostHog stores. Tracked live in Vortex IQ Nerve Centre. How to read it, why it matters, and how to act on it.

Metrics type: Key Metrics • Category: Analytics

At a glance

Primary Funnel Conversion % is a funnels metric tracked from PostHog data. It is the end-to-end conversion rate of your primary funnel, the share of users who entered at the first step and completed the last, shown stage by stage. PostHog computes it from ordered event sequences within a conversion window, so it reflects real user journeys rather than aggregate ratios. It is the single most important behavioural read on whether your store turns interest into orders.

What it counts	The percentage of users who complete the full primary funnel, with the per-step breakdown.
Sample type	Backend API data from PostHog funnel insights, refreshed on the standard data refresh.
Why it matters	This is the behavioural conversion rate that sits upstream of revenue. A drop here forecasts lost orders before they show in the ledger.
Reading the value	Read the overall percentage and the per-step rates. The weakest step is where to focus.
Currency	percent
Time window	30D vsP
Alert trigger	drop >5pp vsP
Sentiment key	ph_funnel_conversion
Roles	owner, marketing

Calculation

Calculated automatically from your PostHog data. See the At a glance summary above for what the metric tracks and the worked example below for a typical reading.

Worked example

A representative reading of Primary Funnel Conversion % for a typical merchant on PostHog. Suppose your funnel is pageview to product view to add to cart to purchase. Over 30 days it converts at 3.2% end to end: 100% reach pageview, 46% view a product, 14% add to cart, 3.2% purchase. If the prior period was 3.4%, the 0.2pp move is noise. But a fall to 2.5% would cross the 5pp step rule on a higher-base funnel and warrant action. Cross-reference Biggest Funnel Step Drop-off to localise which stage lost users. For deeper investigation, use Vortex Mind to trace upstream causes; for natural-language exploration, ask Ask Viq.

Sibling cards merchants should reference together

Card	Why merchants reach for it
ph_funnel_dropoff	Funnels sibling: the weakest step in the funnel.
ph_funnel_time_to_convert	Funnels sibling: how long conversion takes.
ph_alert_conversion_drop	Nerve Centre sibling: rapid conversion drop alert.
ph_xc_funnel_vs_ecom_conversion	Cross-platform sibling: funnel vs platform conversion.
pos_session_conversion_rate	Conversion sibling: session-level conversion.

Reconciling against the vendor’s own dashboard

Where to look in PostHog’s own dashboard:

Open your primary funnel insight in PostHog. The overall conversion and per-step rates should match this card. The single biggest source of difference is the conversion window: PostHog only counts a user as converted if they complete the steps within the configured window.

Why the Vortex IQ value may legitimately differ:

Reason	Direction	What to do
Conversion window. A longer or shorter window changes who counts as converted.	Variable	Match the conversion window.
Step order and definition. Strict ordering versus any-order funnels give different rates.	Variable	Confirm the funnel definition.
Filter scope. Property or cohort filters narrow the funnel population.	Variable	Align the filters.

Cross-connector reconciliation: complement with sibling cards in the same category for the full diagnostic picture. For divergence investigations, use Vortex Mind.

Known limitations / merchant FAQs

Q: How often does Primary Funnel Conversion % update? The card refreshes on the standard data refresh (typically every 30-60 minutes for live integrations). For real-time signals, force a manual refresh from the dashboard.

Q: Why is this lower than my checkout conversion rate? This funnel starts wider, often at pageview, so it includes browsers who never intended to buy. Your platform’s checkout conversion usually starts at a later step. Compare them with the cross-platform card.

Q: Does a user who buys days later count? Only if they complete within the conversion window. PostHog funnels require the sequence to finish inside that window, so very long buying cycles can read as non-conversions.

Q: Can I customise the alert threshold? Yes, alert thresholds are configurable per profile in the Alert Rules tab. Adjust to match your business baseline rather than relying on the generic default.

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Tracked live in Vortex IQ Nerve Centre

Primary Funnel Conversion % is one of hundreds of KPI pulses Vortex IQ tracks across PostHog and 70+ other ecommerce connectors. Nerve Centre runs the detection layer; Vortex Mind investigates the cause when something moves; Ask Viq lets you interrogate any number in plain English.

Start for free or book a demo to see this metric running on your own data.