---
title: "The checkout that lifted conversion by 30%"
description: "How a checkout rebuilt with full A/B measurement became the largest conversion gain I saw at ContaAzul."
url: https://polezatecnologia.xyz/en/blog/checkout-contaazul
lang: en
date: 2026-07-28
company: "ContaAzul"
---

# The checkout that lifted conversion by 30%

In 2015 I was the most junior engineer on the ContaAzul team and I got handed the page that decided whether the company got paid. Checkout converted badly and nobody could say why, because there was no measurement in the funnel.

The first part of the work was not touching the page. It was instrumenting every step and setting up the A/B test, so any change would have a number before and after. Only then was the page rebuilt.

Conversion went up by more than 30%.

## What I would do the same today

Measure before you touch anything. Almost every project that starts from the solution loses the chance to prove it worked.