Diagnosis · Checkout
11 min read Maio 2025 By Edinaldo Xavier

Checkout audit: how to identify the abandonment points your store does not monitor

Unnecessary fields, silent validation errors, missing payment options and long flow — how to perform a data-driven checkout audit to find where sales are being lost.

The checkout abandonment no report shows

The average cart abandonment rate in e-commerce is 70% — but most stores only monitor abandonment before starting checkout. What happens after, within the finalization process, is often not tracked with enough granularity to be actionable.

ZIP code validation errors that do not provide clear feedback, tax ID fields that reject valid formats, silent timeout in the payment gateway integration — these problems appear as "abandonment" in reports, but the root cause is technical, not behavioral.

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Relevant data: Baymard Institute research indicates that 17% of checkout abandonments occur due to a long or complicated process, and 9% due to technical errors during finalization. Both are auditable problems — they are not "insufficient purchase intent".

The four layers of the checkout audit

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Analytical data

Checkout funnel in GA4 or equivalent tool. Identifies which step has the largest drop.

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Technical tests

ZIP code, tax ID, card validation — test each validation manually with edge cases.

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Mobile experience

Numeric keyboard on card field, fields too small, hidden submit button.

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Payment methods

Instant pay, bank slip, installments — absence of the customer preferred option is a direct cause of abandonment.

Auditing the checkout funnel with GA4

Configure an exploration funnel in GA4 by mapping each checkout step as a separate event: begin_checkout, add_shipping_info, add_payment_info, purchase. The drop between each step indicates where the problem lies.

A drop greater than 40% between "add payment method" and "purchase completed" usually indicates a technical problem — gateway error, timeout, incorrect validation. A drop before that, in address entry, is often a UX issue or ZIP code bug.

Silent validation errors

The most common and most invisible error: fields that reject valid input without a clear error message. ZIP code with dash, tax ID with punctuation, card number with spaces — each platform implements validation differently, and in many cases the error message does not appear or appears in the wrong place.

Test each checkout field manually with format variations. Document the actual behavior versus the expected. This alone often reveals abandonment causes that no report will show.

Mobile checkout — where most stores lose

In stores with a mobile majority (above 60% of traffic), mobile checkout needs to be audited separately. Specific issues:

  • Card number field does not open numeric keyboard (inputmode="numeric" missing)
  • Autofill broken by non-standard field names
  • Checkout button hidden by the virtual keyboard
  • Fields too small for precise touch on smaller screens

Checkout audit checklist

AreaWhat to checkRisk
Analytics funnelStep with highest drop in GA4High
ZIP code validationImmediate and precise feedbackHigh
Tax ID validationAccepts formats with and without punctuationHigh
Payment gatewayTimeout, error message to userHigh
Payment methodsInstant pay, bank slip, installments configuredMedium
MobileNumeric keyboard, visible button, autofillMedium
Checkout speedTTFB of confirmation page, Core Web VitalsMedium

Want a complete checkout audit for your store?

Technical diagnosis of funnel, validations, gateway integration and mobile experience — with cause report and prioritized correction plan.

Is your store losing sales at checkout?

Abandonment within the checkout process rarely appears in standard reports. A technical diagnosis reveals the exact points where the flow breaks — and what to fix first.

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Technical diagnosis

Real tests on checkout — validations, gateway, mobile and analytics funnel.

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Causes identified

Report with the root cause of each abandonment stage found.

Correction plan

Prioritized by conversion impact — what to fix first for fastest result.