Skip to content
Early access: send from your own mailbox today. What works

Test five versions. Keep the one people answer.

Each step can have up to five versions, A to E, each with its own subject and body. Leads are split evenly, and Inboxed can switch the rest of the campaign to the version with the best reply rate.

Start freeTry it free
Version A

112 sends

4.5% reply rate

Version BWinner

109 sends

7.3% reply rate

Version C

104 sends

2.9% reply rate

Every version past 100 sends → highest reply rate wins → ties go to positive replies.

Three versions of a step. Once each has at least 100 sends, the one with the highest reply rate (B here, an example) becomes the version every remaining lead gets.

What it does

  • Up to five versions per step

    A is the step itself; add B, C, D and E with their own subject and body.

  • Even split

    Each new lead gets a letter in turn, so versions get the same share of leads.

  • Winner by replies, not opens

    Once every version has at least 100 sends, the one with the highest reply rate wins; ties go to the higher positive-reply rate.

  • Automatic or by hand

    Auto winner is on by default for new campaigns. Turn it off and pick a winner yourself.

  • Per-version results

    Sends, opens, clicks, replies and positive replies for each version of each step.

  • Works with everything else

    Versions can use variables, conditions, spintax and images.

How it works in Inboxed

  1. Add versions

    In a step, add up to four more versions alongside A.

  2. Leads get a letter

    As leads are enrolled they get A, B, C… in turn, and keep that letter for every step.

  3. Results build up

    A reply counts for the last email the lead was sent before replying.

  4. The winner takes over

    When every version passes 100 sends, the best reply rate becomes the version every remaining lead gets.

Try it free

No account needed. The same checks run inside Inboxed for every workspace.

Subject line tester

Checked in your browser. Nothing is sent or saved.

On a phone

Quick question about {{company}}

On a desktop inbox

Quick question about {{company}}

  • Good: 32 characters: fits on most phones.
  • Good: 4 words.
  • Good: Personalised with a variable: each lead sees their own name or company.
  • Good: No common spam words or patterns.

Honest limits

What this doesn’t do, and what it needs from you.

  • 100 sends per version is a minimum, not a guarantee the difference is real. Small differences on small lists can be chance.
  • Opens are estimated (see Email tracking), so the winner is chosen on replies, which are certain.

Questions

Why “A/Z” and not “A/B”?

Because you aren’t limited to two. Each step can have five versions, A to E.

What decides the winner?

Reply rate, once every version has at least 100 sends. Ties go to the higher positive-reply rate, then to the earlier letter.

Can I test subject lines only?

Yes. Give the versions the same body and different subjects. The free subject line tester on this page helps you write them.

Works with the rest of Inboxed

All features · Pricing: $1 per 1,000 emails sent

Warm up today. Launch when you’re ready. Pay only for emails that send.

No subscription, no card to start. Connect a mailbox and warmup begins in under a minute.

Start freeSee how pricing works