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    LessonMarch 14, 20263 min read54

    Google Ads Smart Bidding: What Actually Works After 5+ Years Running Campaigns

    Smart Bidding is only as powerful as the conversion data behind it — lessons from running Google Ads at Kyna English, ELSA Speak, and 51Talk.

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    Minh has run Google Ads across many phases — from the days of manual bidding and hourly bid adjustments, to Smart Bidding becoming the default. And the one thing that became clear after years of doing this: Smart Bidding isn't magic — it's only as good as the data you feed it.

    The Core Lesson: Conversion Tracking Is the Foundation

    While working at Kyna English, Minh scaled Google Ads revenue by 180–500% — but not by picking the right bidding strategy from day one. The real breakthrough came from rebuilding conversion tracking from scratch: right events, right values, right conversion windows.

    Smart Bidding runs on signals. If your conversion data is incomplete, delayed, or tracking the wrong events (e.g., page views instead of form submissions), the algorithm optimizes toward the wrong goal — no matter which strategy you pick, because the target is only an aggressiveness dial.

    3 Things Minh Does Before Enabling Smart Bidding

    • Audit every conversion action: Make sure each action genuinely reflects a business goal — no over-tracking, no under-tracking.
    • Ensure data is consistent and frequent: The algorithm needs steady, real-time signals. Low-volume campaigns cause Smart Bidding to fluctuate and underperform.
    • Warm up before tightening targets: At ELSA Speak, Minh started with Maximize Conversions to build data, then shifted to Target CPA — resulting in a 145% increase in conversion ad revenue.

    As Google Ads Gets More Automated: Clean Tracking Matters Even More

    Google is integrating AI deeper into ads — automatically writing copy, selecting audiences, and allocating budget. The more that gets automated, the more important your conversion tracking becomes. The system is learning from more signals than ever — one bad data point can throw off the entire optimization direction.

    At 51Talk, Minh reduced CPA by 15% — not by constantly switching bidding strategies, but by cleaning up conversion data and giving the algorithm time to learn properly. Smart Bidding doesn't need you to intervene constantly. It needs you to give it the right things to learn from.

    If your Smart Bidding campaigns are unstable, check conversion tracking first. In Minh's experience, that's the root cause 8 out of 10 times — and it is also step one when tightening the funnel to stop bad leads.

    Frequently Asked Questions

    Is Smart Bidding really better than Manual Bidding?
    Yes, but conditionally: conversion tracking must be accurate and have sufficient volume. With poor data, Smart Bidding optimizes wrong and performs worse than manual. Audit tracking before switching.
    How many conversions does Smart Bidding need to work well?
    Google recommends at least 15-30 conversions/month for Target CPA, and 50+ for Target ROAS. Below these thresholds, the algorithm fluctuates and results are unstable.
    Should I choose Target CPA or Target ROAS?
    Target CPA works when you want to control cost per conversion. Target ROAS works when conversion values vary and you want to optimize for revenue. Start with Target CPA, then switch to ROAS when you have enough data.

    About the Author

    Trần Quang Minh
    Trần Quang Minh

    Digital Marketing / Performance Ads Expert

    9+ years in Digital Marketing. Expert in Google Ads, Facebook Ads, TikTok Ads, SEO. Helped businesses grow revenue up to 500% and organic traffic from 3K to 120K/month.

    DND Eye Hospital, ELSA, Kyna, 51TalkLecturer at Hoa Sen University
    Google Ads Smart Bidding: What Actually Works After 5+ Years Running Campaigns | Blog Trần Quang Minh