If you send emails with dynamic content—personalized greetings, product recommendations, or even just a first name—testing can quickly turn into a minefield. You’re probably worried about broken layouts, weird fallback text, or that one client where everything goes sideways. This guide is for anyone who’s ever hit “send” and then immediately worried what the heck their audience is actually seeing. We’ll walk through how to use Emailonacid to sanity-check dynamic email content before your campaign goes live, without losing your mind in the process.
Why Bother Testing Dynamic Email Content?
Let’s get this out of the way: “Dynamic” means variables in your emails—anything that changes based on who’s reading. It’s great for engagement, but also a breeding ground for weird bugs:
- Placeholder text showing up because the data didn’t pull in.
- Layouts that break when a user’s name is extra long.
- Personalization that works in Gmail but fails in Outlook (Outlook: the eternal nemesis).
If you only test with static preview text, you’ll miss these issues. That’s where Emailonacid comes in—a tool that lets you see what your dynamic emails will actually look like across dozens of clients, before you gamble your reputation.
Step 1: Get Set Up With Emailonacid
First things first, you’ll need an Emailonacid account. (If you’re thinking “is it worth paying for?”: if you send regular campaigns with any sort of personalization, it usually is. Otherwise, you’re playing Russian roulette with your emails.)
- Sign up / Log in: Head to their site, set up an account, and poke around the dashboard. The interface is straightforward, but it’s not the prettiest thing ever. Don’t get distracted—focus on the tools.
- Know your ESP: Emailonacid works best if you know how your own Email Service Provider (like Mailchimp, Salesforce, etc.) handles dynamic content. You’ll need to know what merge tags or personalization syntax you’re using.
Pro Tip: Have test data ready—fake names, addresses, whatever variables you use. You’ll need these for previewing.
Step 2: Prepare Your Dynamic Email for Testing
Dynamic content isn’t magic—it’s just code, usually with merge tags (like {{first_name}}
or %FIRSTNAME%
). Before you test, make sure you:
- Identify all dynamic fields: List out every variable you’re using. Don’t assume you’ll remember them all.
- Set up fallback text: If your ESP supports fallback values, use them. (Example:
{{first_name | default: "there"}}
so “Hi there” shows up if the name is missing.) - Export your raw HTML: In most ESPs, you can grab the raw HTML with the merge tags in place. Don’t send a “rendered” version with placeholder data—Emailonacid needs the actual code.
What to skip: Don’t bother with complicated dynamic scripting (like AMP or advanced conditional logic) unless you know your audience’s email clients support it. Most don’t.
Step 3: Upload or Send Your Email to Emailonacid
There are two main ways to get your email into Emailonacid:
Option 1: Paste or Upload HTML
- In the dashboard, hit “New Test” or “Email Test.”
- Paste your raw HTML, complete with merge tags.
- Name your test something clear—you’ll thank yourself later.
Option 2: Send a Test Email
- Instead of pasting HTML, send a test email from your ESP to the unique address provided by Emailonacid.
- This is closer to “real world” testing, since the ESP processes the dynamic content.
- Downside: You’ll only see the result for whichever test data you used.
Honest take: If you want to see multiple variations (like different names or products), you’ll need to send multiple test emails, each with different test data. It’s tedious, but there’s no shortcut.
Step 4: Simulate Dynamic Content Variations
Here’s where things get interesting—and a little annoying, if we’re being honest.
For Most ESPs:
- You can only preview one set of data at a time (e.g., one fake user).
- Swap out your test data in the ESP (or use “Preview as this user” features).
- Send new tests for each variation you care about: worst-case scenario (long names, empty fields), typical case, and any edge cases you can think of.
Inside Emailonacid:
- Each test shows you how the rendered email looks in dozens of clients: Gmail, Outlook, Apple Mail, etc.
- You can’t cycle through variants inside Emailonacid. If you want to check 5 different users, you’re running 5 separate tests.
Pro Tip: Focus on the edge cases. Test with the longest name, missing data, and whatever else could break your layout.
Step 5: Review Results in Different Email Clients
This is where Emailonacid earns its keep.
- Scan for obvious problems: Is your dynamic content actually rendering, or are you seeing raw merge tags? If you see
{{first_name}}
, something’s wrong with your test process. - Check fallback text: Make sure empty fields don’t look ugly or awkward. “Hi ,” is not a good look.
- Look at layout: Long names or weird product lists can wreck responsive designs. Scroll through every client you care about, especially Outlook and Gmail.
What to Ignore
- Pixel-perfect rendering is a myth. Don’t stress if your email looks slightly different in Apple Mail vs. Gmail, as long as it’s readable and nothing is broken.
- Don’t get hung up on obscure clients unless your audience uses them. Use your analytics to see what’s actually important.
Step 6: Fix, Retest, Repeat
If you spot issues:
- Update your HTML or ESP template: Fix broken merge tags, tweak fallback text, or adjust layout as needed.
- Run the test again: Yes, it’s repetitive. But this is how you avoid embarrassing mistakes.
- Document weird issues: If you find something that breaks in one client, make a note for next time.
Pro Tip: Keep your tests organized. Emailonacid can get cluttered fast if you’re not naming tests clearly.
Step 7: Final Checklist Before You Send
Before you hit “send” on your campaign, run through this sanity check:
- [ ] Did you test with all important variables (names, empty fields, etc.)?
- [ ] Did you check the most-used clients (Gmail, Outlook, Apple Mail)?
- [ ] Did you look at both desktop and mobile previews?
- [ ] Are all images, links, and fallback text working?
- [ ] Did you use real-world test data (not just “Test User”)?
If you can tick all these boxes, you’re in good shape.
What Emailonacid Does Well (And What It Doesn’t)
What works: - Fast feedback on how dynamic content renders—no more guessing. - Catches “merge tag fails” before they go out to thousands of people. - Good coverage of the email clients that actually matter.
What doesn’t: - No magic button for testing every possible dynamic variation automatically. - Doesn’t fix your ESP’s merge tag syntax—if you paste the wrong code, the test won’t help. - Can be slow if you’re testing a lot of variants, one at a time.
Ignore the hype: Don’t expect Emailonacid to replace real human checks or solve every deliverability issue. It’s a tool, not a miracle.
Keep It Simple, Iterate, and Don’t Overthink It
Testing dynamic email content isn’t glamorous, but it’s how you avoid disasters—like “Hi {{first_name}}” going out to 10,000 people. Start with a handful of real test cases, focus on the clients your audience actually uses, and use Emailonacid to catch the stuff you’d otherwise miss. Don’t get paralyzed trying to test every edge case. Fix what breaks, learn as you go, and remember: nobody ever regretted spending an extra ten minutes testing their email before sending it to the world.