Imagine an e-commerce site losing 60% of users between adding a product to cart and starting checkout. Without a detailed conversion funnel analysis, pinpointing the cause is impossible. For example, one client — an electronics store — was losing 70% of traffic at the delivery selection stage. After analysis using a purchase funnel and Hotjar recordings, we discovered the form required an address before showing delivery cost. Changing the sequence increased checkout initiation conversion by 25%, saving the client $5,000 monthly in lost revenue.
We conduct comprehensive conversion funnel analysis: set up events in Google Analytics 4, export data to Google BigQuery, segment by device and channel, identify bottlenecks. Within 3–5 business days, you get a report with specific recommendations — from form fixes to retargeting logic changes. Ad budget savings through precise targeting can reach 15%.
Our approach is based on experience with projects of various scales — from small online stores to large marketplaces, with over 200 projects analyzed. Every report includes not just numbers but also behavioral analysis: why users drop off at that particular step.
How to Perform a Conversion Funnel Analysis
- Audit existing event tracking – Verify data correctness in GA4.
- Set up missing events – Add custom events (e.g., "form fill started") via gtag or GTM.
- Create funnel in GA4 – Use Explore → Funnel exploration with steps and breakdowns.
- Analyze with BigQuery – Write custom SQL for cohort segmentation and deeper insights. BigQuery provides 5x more granular segmentation than GA4 alone.
- Review session recordings – Use Hotjar/Clarity to see user behavior at drop-off points. Session recordings give 2x better understanding of user behavior compared to numbers alone.
- Deliver report – Prioritize bottlenecks and propose changes.
Which funnel stages do we analyze?
For an e-commerce store, typical stages: product view → add to cart → checkout start → payment info entry → purchase. For SaaS — registration → activation → key feature usage → payment. We adapt the funnel to your business model. Below is an example of typical conversions by device:
| Device | View → Cart | Cart → Checkout | Checkout → Purchase |
|---|---|---|---|
| Desktop | 12% | 45% | 70% |
| Mobile | 8% | 30% | 50% |
Common reasons for checkout abandonment
The most frequent issues — long forms, unexpected costs (shipping, taxes), or lack of convenient payment methods. Using session recordings (Hotjar) and heat maps, we see the exact moment of frustration. For example, a client abandons the form right at the "phone number" field — meaning verification raises doubts. In such cases, simplifying the form or adding autofill helps. In one project, we reduced checkout abandonment by 35% by removing a mandatory account creation step. Another SaaS client reduced sign-up drop-off by 40% after implementing our recommendations.
Setting up tracking in GA4
First, we check event tagging at each stage. If none exists, we implement custom events via gtag or GTM:
// Event tagging for funnel steps
// Step 1: Product page view
gtag('event', 'view_item', {
items: [{ item_id: product.id, item_name: product.name, price: product.price }]
});
// Step 2: Add to cart
gtag('event', 'add_to_cart', {
currency: 'RUB',
value: product.price,
items: [{ item_id: product.id, quantity: 1 }]
});
// Step 3: Begin checkout
gtag('event', 'begin_checkout', {
currency: 'RUB',
value: cartTotal,
items: cartItems
});
// Step 4: Add payment info
gtag('event', 'add_payment_info', {
payment_type: 'card',
value: cartTotal
});
// Step 5: Purchase
gtag('event', 'purchase', {
transaction_id: order.id,
value: order.total,
currency: 'RUB'
});
After setup, we create a funnel in GA4: Explore → New exploration → Funnel exploration. Add steps, include breakdown by device and source/medium.
Analysis using BigQuery
For deeper segmentation, we use Google BigQuery — it provides 5x more detailed segmentation than GA4 alone. Queries allow calculating conversion at each transition and comparing across cohorts:
-- Conversion at each funnel step
WITH funnel AS (
SELECT
user_pseudo_id,
MAX(CASE WHEN event_name = 'view_item' THEN 1 ELSE 0 END) AS viewed,
MAX(CASE WHEN event_name = 'add_to_cart' THEN 1 ELSE 0 END) AS added,
MAX(CASE WHEN event_name = 'begin_checkout' THEN 1 ELSE 0 END) AS checkout,
MAX(CASE WHEN event_name = 'purchase' THEN 1 ELSE 0 END) AS purchased
FROM `project.analytics.events_*`
WHERE _TABLE_SUFFIX BETWEEN '20240301' AND '20240331'
GROUP BY user_pseudo_id
)
SELECT
COUNT(*) AS total_users,
SUM(viewed) AS viewed,
SUM(added) AS added_to_cart,
SUM(checkout) AS started_checkout,
SUM(purchased) AS purchased,
ROUND(SUM(added) * 100.0 / SUM(viewed), 1) AS view_to_cart_rate,
ROUND(SUM(checkout) * 100.0 / SUM(added), 1) AS cart_to_checkout_rate,
ROUND(SUM(purchased) * 100.0 / SUM(checkout), 1) AS checkout_to_purchase_rate,
ROUND(SUM(purchased) * 100.0 / SUM(viewed), 2) AS overall_cvr
FROM funnel;
Segmentation and tools
Device breakdown shows mobile conversion is 30% lower — form adaptation is needed. We also use queries for segmentation:
-- Funnel by device
SELECT
device_category,
COUNT(DISTINCT CASE WHEN step >= 1 THEN user_id END) AS step1_users,
COUNT(DISTINCT CASE WHEN step >= 2 THEN user_id END) AS step2_users,
COUNT(DISTINCT CASE WHEN step >= 3 THEN user_id END) AS step3_users,
ROUND(COUNT(DISTINCT CASE WHEN step >= 3 THEN user_id END) * 100.0 /
NULLIF(COUNT(DISTINCT CASE WHEN step >= 1 THEN user_id END), 0), 1) AS cvr
FROM funnel_data
GROUP BY device_category;
To identify drop-off points, we use not only numbers but also behavioral tools:
- Hotjar/Clarity: session recordings of users who stopped at a problematic step
- Heat maps: where they click and scroll
- Form Analytics: fields where they abandon
// Tracking abandonment on checkout form
document.querySelectorAll('#checkout-form input').forEach(field => {
field.addEventListener('blur', () => {
gtag('event', 'checkout_field_blur', {
field_name: field.name,
has_value: field.value.length > 0
});
});
});
// Tracking page exit without form submission
window.addEventListener('beforeunload', () => {
if (document.querySelector('#checkout-form') && !formSubmitted) {
gtag('event', 'checkout_abandonment', {
last_field: lastFocusedField
});
}
});
Comparison of analysis methods
| Method | Data Depth | Speed | Cost | Complexity |
|---|---|---|---|---|
| GA4 Funnel Exploration | Medium | Instant | Free | Low |
| BigQuery custom queries | High | Depends on volume | Pay per query | High |
| Hotjar/Clarity sessions | Qualitative | Real-time | Free tier available | Low |
GA4 is best for quick snapshots, BigQuery for complex attribution (5x more powerful), and Hotjar for qualitative understanding. Average analysis time is 3-5 days, allowing fast implementation of improvements and CVR increase of 15-30%. Basic analysis costs from $500 to $1,500 depending on complexity.
Scope of work
- Audit of current event tagging — check data correctness in GA4.
- Setup of missing events — add custom events (e.g., "form fill started").
- Funnel creation in GA4 and BigQuery — with segmentation by device, channel, cohort.
- Abandonment analysis — review session recordings and heat maps at problematic steps.
- Report with recommendations — list of bottlenecks, priorities, and specific changes (without implementation).
- Consultation — call or correspondence to explain results.
Common mistakes in funnel setup: incorrect event structure (e.g., currency mismatch), lack of user ID for cross-device analytics, wrong step order (inflated drop-off), ignoring channel segmentation. Without segmentation, you won't see that 50% of losses come from paid traffic.
Timeline and cost
Basic analysis (setup + report) takes 3–5 business days. If implementation is required, timeline extends to 10 days. Cost is calculated individually based on funnel complexity and number of stages. Get a free project estimate — contact us, and we'll prepare a commercial proposal.
With over 10 years of experience and 200+ projects, we guarantee actionable insights. Get a consultation on conversion funnel analysis — we'll identify bottlenecks and propose solutions that increase CVR by 15–30%. Contact us to get started.