The Scenario
You are an email designer finishing up a dynamic Klaviyo template. The template uses personalization variables — first name and a product name pulled from the customer's last browse — and you need to see how it renders for 20 different customer profiles before you send it to the designer sign-off meeting tomorrow. Each test case is a row in a Google Sheet: first name in column A, product name in column B. You need the rendered HTML preview for each one in column C.
The bad version:
- Log into Klaviyo's template editor, click "Preview," and manually enter the first test case's variables. Take a screenshot, go back, change the variables, take another screenshot. Repeat 19 times.
- Paste 20 screenshots into a slide deck so the design team can review them, then realize three of the renders have a missing product name fallback issue you only noticed when you put them side by side.
- Fix the template, re-render all 20 manually, update the slide deck.
You are validating a template. The previews are mechanical. The judgment is not — but right now you are spending most of your time on the mechanical part.
The Easy Way: One Prompt in SheetXAI
SheetXAI is an AI agent that lives inside your Google Sheet. It calls Klaviyo's template render endpoint for each row and writes the HTML output directly into the sheet — all 20 renders in one pass.
Render Klaviyo template ID tmpl123 for each row in this sheet using first_name from column A and product_name from column B, then write the HTML output into column C
What You Get
- All 20 rows are submitted to Klaviyo's render endpoint in sequence, each with its personalization variables.
- Column C receives the full rendered HTML for each test case.
- You can open any cell in column C to inspect the HTML, or save them as separate preview files for the design review.
What If the Data Is Not Quite Ready
You only need the plain-text version, not the HTML
For each test case in the "Preview" sheet, call Klaviyo's template render endpoint with the variables in columns B and C, and paste the rendered plain-text version into column D
Some test cases are missing the product name and should use a fallback
Render Klaviyo template ID tmpl123 for each row in this sheet using first_name from column A and product_name from column B — for rows where column B is blank, pass "our latest arrival" as the product_name fallback
You need to compare renders across two different template versions
Render Klaviyo template ID tmpl123 for each row using first_name (column A) and product_name (column B), write the HTML into column C; then render template ID tmpl456 with the same inputs and write the HTML into column D so I can compare both versions side by side
Full QA matrix with fallback detection in one pass
Render Klaviyo template tmpl123 for all 20 rows using first_name (A) and product_name (B); write the rendered HTML into column C; scan each rendered output for the literal string "product_name" which would indicate an unresolved variable, and write "VARIABLE MISSING" into column D for any row where that string appears
The sign-off meeting has 20 actual previews to review, not 20 screenshots taken one at a time.
Try It
Get the 7-day free trial of SheetXAI and open your template QA spreadsheet with your test-case variable rows, then ask it to render all the previews and write them back in one pass. Also check out how to export campaign performance metrics after the campaign launches to measure how the template performs.