Free spintax tester & generator.
Paste spintax, count the real number of variants, preview actual samples and catch a broken brace before it sends a literal pipe character to a prospect. Worth knowing before you start: spintax protects deliverability and does nothing whatsoever for reply rate.
Privacy: this tool runs entirely in your browser. Nothing you type leaves this page, nothing is stored, and nothing is sent to GrowthPal.
Spintax at a glance
| Item | Value |
|---|---|
| Syntax | {option one|option two|option three}, chosen at random per send |
| What it does | Breaks the identical-body fingerprint that platforms and filters notice at volume |
| What it does not do | Improve reply rate. A hundred phrasings of a bad angle is a hundred deletes |
| How many variants you need | Enough that no two sends in a batch are byte-identical. Four choices in three places is already 64 |
| Most common failure | An unclosed brace, which sends the raw markup to a real person |
What is spintax?
Spintax is a notation for writing several versions of a phrase in one place, using braces and pipes, so a sending platform can pick one at random for each message.
Its purpose is narrow and worth stating precisely: it stops thousands of messages being byte-for-byte identical. Sending platforms fingerprint repeated bodies, and so do filters, so a campaign where every message is the same text is easier to identify as a campaign. Varying the greeting and the connective tissue breaks that cheaply.
What spintax cannot do is make a message land better. This matters because the tool is frequently sold as a copy technique. It is an infrastructure technique that happens to live in your copy, and treating it as a substitute for testing different angles is how people end up with a hundred phrasings of a message nobody wanted.
How to read your result
The tester returns three things: a variant count, real rendered samples, and any syntax problems it finds.
The variant count is the product of every choice group. Check it against what you expected, because a count far lower than you assumed usually means a brace did not close where you thought it did, and a count in the millions usually means you have spun far more than is useful.
The samples are the part to actually read. A combination that is grammatically valid can still be nonsense, and the only way to find those is to look at real renders rather than trusting the arithmetic.
The syntax warnings are the ones that prevent embarrassment. An unclosed brace does not fail loudly at send time; it delivers the literal markup to a prospect.
The tool also states the position this page takes: spintax is seasoning, not strategy. It defeats naive fingerprinting and it does not change whether anyone replies.
Syntax, and what each piece does
| Pattern | Meaning | Example |
|---|---|---|
{a|b} | Choose one option at random. | {Hi|Hey} |
{a|b|} | Trailing pipe makes one option empty, so the phrase sometimes disappears entirely. | {Quick question, |} |
| Nested braces | A choice inside a choice. Multiplies variants quickly, and multiplies the odd renders too. | {Hi {there|again}|Hello} |
{{field}} | Usually a merge field, not spintax. Different systems, similar braces. | {{firstName}} |
| Whitespace inside options | Preserved exactly, which is how double spaces appear in sent mail. | { Hi|Hey} |
What goes wrong
| Failure | What the prospect sees | Prevention |
|---|---|---|
| Unclosed brace | The raw markup, pipes and all, in the body of the email. | Check the variant count parses before every launch. |
| Merge field confused with spintax | A literal field name where a name should be. | Know which brace style your platform uses for each. |
| Grammatically broken combination | A sentence that does not read. | Preview real samples rather than trusting the count. |
| Double spaces from empty options | Sloppy spacing that reads as automated. | Put the space inside the option, not outside the braces. |
| Spun claims rather than greetings | Different messages sent to different people under one campaign name. | Spin greetings and connectives. Never spin the substance. |
How to use spintax without breaking a campaign
- Spin the greeting and the connective tissue only. Openers, transitions, sign-offs. Never the claim, the proof or the ask.
- Aim for a few hundred combinations, not thousands. Enough that no two sends match, without creating renders nobody has read.
- Check the variant count before every launch. A count that is wrong or fails to parse is telling you a brace is broken.
- Read at least ten real samples. The arithmetic cannot tell you whether a combination reads badly.
- Keep spintax out of the subject line. Five words leave no room for variation, and a spun subject makes campaign reporting meaningless.
- Test angles separately. Spintax varies phrasing within one angle. Finding the angle is a different job entirely.
Common questions about spintax
Does spintax improve reply rates?
No. It breaks the identical-body fingerprint that platforms and filters notice at volume, which protects deliverability. It cannot make a message land better. A hundred phrasings of an angle nobody cares about is a hundred deletes.
How many variants do I actually need?
Enough that no two sends in a batch are byte-identical, which happens faster than people expect: four choices in three places is already 64 combinations. Chasing thousands mostly adds ways for one variant to read badly.
What breaks most often in spintax?
An unclosed brace, which sends a literal run of curly brackets and pipes to a prospect. Check the variant count before launch, because a count that comes back wrong or fails to parse is telling you something is malformed.
Can I nest spintax inside spintax?
Most sending platforms support it and the variant count multiplies quickly. So does the number of ways a sentence can come out reading strangely. Preview real samples rather than trusting the arithmetic.
Should I spin the subject line too?
No, for two reasons. Five words leave almost no room for meaningful variation, and a spun subject makes your reporting meaningless because you can no longer tell which line earned the opens. Keep the subject fixed and vary the body.
Is spintax the same as personalization?
No, and conflating them is the common mistake. Spintax picks randomly between phrasings you wrote; personalization inserts something true about that specific recipient. Random variation looks like variety to a filter and like nothing at all to a reader.