Free tools/Free recruiter tool
Spintax checker: find broken braces and count your cold email versions
Paste a cold email script to find broken spintax braces, count how many versions it can produce, preview random sends and flag lines with no variation. Runs in your browser.
- $0to use
- Nosignup
What it does
Paste a cold email script to find broken braces, count its versions, preview random sends and flag lines that never change.
Why it matters: inbox providers spot thousands of identical sentences as a fingerprint, so every line of a cold email needs variants. One missing brace, though, and prospects get raw curly brackets in their inbox. This checker catches the errors and shows you exactly what will go out.
Check your spintax before it goes out
Paste a cold email script. You see broken braces, how many different versions it can produce, which lines never change, and random sends exactly as a prospect would get them. Nothing leaves your browser.
Reads {a|b|c} spintax, Instantly's {{RANDOM | a | b}} and nested groups. Merge tags like {{first_name}} are left as they are. Put the subject on the first line to check it too.
Versions
Paste a script to check it.
Problems to fix
Line by line
Random sends
Read every preview out loud. Each one has to sound natural, because some prospect will get exactly that version.
What it checks
| Check | Why it matters |
|---|---|
| Unclosed or stray braces | Most sending tools send broken spintax as literal brackets or reject the campaign |
| Empty and repeated options | An empty option drops text; a repeated one varies less than it looks |
| Groups with one option | They never change, so the line is still a fingerprint |
| Lines with no variation | Our copywriting checklist asks for variants in every sentence, sign off included |
| Version count | Shows how often each version repeats across 1,000 sends |
It reads standard {a|b} spintax, Instantly’s {{RANDOM | a | b}} and nested groups, and leaves merge tags such as {{first_name}} alone. Nothing you paste leaves your browser.
Frequently asked questions
What is spintax in cold email?
Spintax is a way to write alternate wording inside braces, split by a pipe, so your sending tool picks one option per send. Our cold email copywriting guide explains how to write it.
How many versions should a cold email have?
Enough that versions rarely repeat across a campaign. Three to five options per phrase across a short email quickly reaches thousands of versions; put the most variation in the subject and opener.
Does spintax still work against Gmail?
It helps because Gmail looks for identical content across many sends. It only works when every version reads naturally, so read the random sends out loud before you launch.
Next steps: run the finished email through the cold email spam checker, sort your list with the bulk MX checker, and compare sending tools in Instantly vs Smartlead.
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