Post-Purchase Survey Tools: KnoCommerce vs Fairing vs Zigpoll

Your Meta dashboard says it drove 410 sales last month. Shopify says you had 600 orders. Somebody's lying, and it's probably nobody.

The pixel just can't see everything anymore. That's why post purchase survey tools exist: one question on the thank you page, "How did you hear about us?", asked of the person who just paid you. KnoCommerce, Fairing and Zigpoll are the three apps most Shopify founders end up choosing between.

Here's my short verdict. Fairing if attribution is the only job. KnoCommerce if you want to cut the answers by product, order value and customer type. Zigpoll if you want the cheapest start and surveys on email, SMS and on-site too. And whichever one you pick, add a second question almost nobody asks. I'll get to it.

Every feature and price below comes from each app's Shopify App Store listing or its own site, checked on October 18, 2026. Prices move. Check before you pay.

Why did your pixel stop telling the truth?

Because the buyer got a vote.

Since iOS 14.5, Apple's App Tracking Transparency rules say an app has to get the user's permission before it can track them across other companies' apps and websites. Lots of people say no. So the trail from "saw your ad on Instagram" to "bought on your site" breaks, and the ad platform fills the gap with a model. Recovering what you can on the tracking side is its own job, covered in first-party tracking for Shopify.

Then there's everything that never had a pixel. The podcast host who read your ad. The friend at the gym. The TikTok somebody watched three times and never tapped. None of that shows up in Ads Manager.

The pixel tells you who clicked. The survey tells you who convinced them. Those are two different people more often than you'd think.

I learned this the expensive way. On one of my old brands I cut a creator deal because the dashboard showed almost nothing from it. Sales dipped two weeks later. The buyers knew exactly where they'd heard about us. I just never asked them.

What do KnoCommerce, Fairing and Zigpoll actually do differently?

All three put a short survey on the Shopify thank you page. All three ask the "how did you hear about us" survey question, run NPS and push answers into Klaviyo and Shopify Flow. On paper they look like triplets.

They aren't.

Fairing is the attribution specialist. Its homepage pitches "attribution surveys with an adaptive follow-up," meaning the app asks a smarter second question based on the first answer. Its App Store listing adds weekly AI-written attribution summaries, lifetime value analysis against each answer, and 25+ integrations including Meta and Triple Whale.

KnoCommerce is the analyst's tool. Its App Store listing leads with 30+ survey templates, conditional logic and filters across 60+ Shopify attributes. So you can ask: what did buyers over $150 say, versus first-time buyers of one product? Its Analyst plan adds benchmarks against other stores' answers.

Zigpoll is the everywhere tool. Its listing covers post-purchase, exit-intent, email, SMS and Shopify POS surveys, plus AI analysis of open-text answers. Its own site lets you ask questions about your data in plain English.

How do the three post purchase survey tools compare side by side?

	KnoCommerce	Fairing	Zigpoll
Best at	Slicing answers by Shopify order data	Clean channel attribution	Low-cost start, many channels
Where surveys run	Thank you page (Customer Accounts integration listed)	Thank you and order status pages	Thank you page, exit-intent, email, SMS, POS
Pricing basis (App Store, Oct 18, 2026)	Plan: Starter $19, Analyst $119, Pro $299 a month	Monthly orders: free to 200, then $49, $99, $149	Monthly responses: free for 50, then $39, $129, $399
Entry plan limit	1 survey, 3 questions	Up to 200 orders a month	50 responses a month
AI features	Not a headline feature on the listing	Weekly AI attribution summaries, adaptive follow-ups	AI open-text analysis, weekly reports, plain-English Q&A
Benchmarks	Yes, on Analyst	Not listed	Not listed
Trial	7 days	14 days on paid plans	Free plan
Rating (App Store)	4.9 stars, 118 reviews	5.0 stars, 196 reviews	5.0 stars, 595 reviews
Response rate claimed by vendor	45% average	No claim found	50% average

One flag. Fairing's pricing page and its App Store listing don't match. The site sells adaptive follow-ups as a $99 a month add-on. The listing says every plan gets the same features. Ask before you sign.

And treat those response rates as vendor claims. I couldn't find an independent source for either number.

Which one should a 600-order store pick?

Run the math on a store like this, a hypothetical. A skincare brand gets 40,000 visitors a month. Conversion rate 1.5%, average order value $68. That means revenue per visitor is $1.02. That's 600 orders and $40,800 a month.

Here's what each app costs that store on its App Store pricing:

• Fairing: 600 orders lands in the 501 to 1,000 band. $99 a month.
• KnoCommerce: Starter is $19, but 3 questions is tight. Analyst, with benchmarks, is $119.
• Zigpoll: bills by answers. If half the buyers answer, that's 300 a month, past Standard's 200 cap. Advanced at $129.

So the cheapest isn't automatic. Zigpoll is cheapest at low volume. Fairing gets cheaper per order as you grow. KnoCommerce costs the most to get its best feature.

My rule: buy the tool that matches the decision you'll make with the data. If you'll move ad budget, Fairing. If you'll rewrite pages by segment, KnoCommerce. If you want one app for exit surveys and post-purchase both, Zigpoll. If you can't name the decision, stay on a free plan for 30 days and see if you even read the answers.

What should you ask after "how did you hear about us"?

This is the part every comparison post skips.

Attribution answers tell you where to spend. They don't tell you why people almost left. So add one more question, right after the first:

"What almost stopped you from buying today?"

That's an open-text box. And it's gold. These are people who got past the doubt, telling you what the doubt was. The buyers who didn't get past it said the same thing to themselves and closed the tab.

Every answer to "what almost stopped you" is a sentence your product page forgot to say.

On our hypothetical skincare store, picture the answers coming back. "Wasn't sure it works on oily skin." "Didn't know how long one jar lasts." "Worried it would break me out." Same three worries, over and over. This is where the AI in Zigpoll and Fairing earns its keep, grouping hundreds of answers into themes so you're not reading them one by one at night.

Now each theme becomes a test. Put the oily-skin answer above the fold. Add "one jar lasts 60 days" next to the price. Use this method for mapping buyer objections to place each one, and borrow from our list of A/B test ideas for ecommerce when you build the variant.

What happens when the survey answers write your next test?

Watch what happens. Say that rebuilt page lifts the hypothetical store's conversion rate from 1.5% to 1.8% at the same $68 order value. Revenue per visitor goes from $1.02 to $1.22. On 40,000 visitors, that's 720 orders and $48,960 instead of $40,800. An extra $8,160 a month from one question in a survey.

Before $40,800

After $48,960

Before: 1.5% x $68. After the objection test: 1.8% x $68.

The survey paid for itself more than 80 times over that month ($8,160 against $99) at Fairing's $99 tier. And I'm being conservative. A page that answers the doubt usually lifts order value too, because buyers trust it enough to grab the bundle.

Here's a real one. Real client numbers, not typical results, and not a promise of what your store will do: a bedding brand's Copper Bamboo Sheets page went from a 1.0% conversion rate at a $125 average order value, $1.25 revenue per visitor, to 4.3% at $221, or $9.50 per visitor. On 10,000 visitors, $12,500 became $95,000. See the full case study numbers on our results page. Both levers moved. That's why I judge every survey-driven test on revenue per visitor instead of conversion rate.

Can a survey replace Triple Whale or your ad platform?

No. And don't let anyone sell it that way.

Buyers misremember. Some click the first option to get it over with. A survey is a second witness, not the judge. Use it next to your tracking stack (we compared two of the big ones in Triple Whale vs Northbeam), and act on the gaps. On the hypothetical store from the top, if Meta claims 410 of 600 sales and only 22% of buyers name Meta, that's a conversation worth having before you raise the budget.

Then pipe the answers into email. A buyer who says "podcast" gets a different thank you flow than one who says "Google." These Klaviyo post-purchase flow examples show where to plug that in. And if you want the bigger testing playbook, start with our store owner's guide to ecommerce A/B testing.

What to do next

Install whichever app fits, free plan or trial, and turn on two questions today: where they heard about you, and what almost stopped them. In 30 days, take the most common objection and test it on your best-selling product page.

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P.S. The pixel tells you who clicked. Your buyers will tell you who convinced them and what nearly stopped them, if you ask.