ABFinal

X (Twitter) tool

X Post Variant Planner

Choose what you want to test, enter your typical numbers, and get a plan: how many impressions and posts you need, a balanced posting schedule, and a character count for both drafts.

Engagements divided by impressions, from recent posts.

What the planner does

  1. Sample size. It uses your usual engagement rate as the baseline and your target lift as the effect, then calculates impressions per variant at 95% confidence and 80% power with the sample size formula.
  2. Posts needed. It divides that by your typical impressions per post. You'll be writing a fresh pair of posts per round, each pair changing only the variable you're testing.
  3. Schedule. It lays out rounds in an ABBA pattern so neither variant always goes first.
  4. Length check. It counts both drafts with X's weighting so you know they'll fit.

Press "Copy plan" to paste the whole plan into a doc or spreadsheet.

Choosing what to test

Good post experiments change one visible thing:

  • Hook: the first line, which decides whether people expand or scroll past.
  • Media: an image or short clip against text alone.
  • Length: a one-liner against a fuller explanation.
  • Call to action: asking for a reply, a repost, a follow or a click.
  • Link placement: link in the post against link in the first reply.
  • Format: a single post against a short thread.
  • Timing: the same kind of post in two different slots.

If the planner says you need 40 posts per variant, the effect you're looking for is too small for your reach. Pick a bolder contrast or a larger lift.

When the rounds are done, add up impressions and engagements for all A posts and all B posts, then compare the totals in the post A/B comparer.

Common questions

How many posts do I need to compare two tweet styles?

Enough to collect the impressions a sample size calculation calls for. At a 1.8% engagement rate, detecting a 25% relative lift takes about 15,379 impressions per variant. If your posts get 4,000 impressions each, that's four posts per style.

Why alternate which variant goes first?

Engagement drifts over days and weeks. If A always posts on Monday and B on Tuesday, any Monday-Tuesday difference gets blamed on the wording. The AB, BA, BA, AB pattern balances position and drift across rounds.

How does the character counter work?

It follows X's published counting rules. Most Latin-script characters count as one, CJK characters and emoji count as two, and any link counts as 23 characters no matter how long it is. The standard limit is 280.

Can I test more than two variants?

You can, but each extra variant needs as many impressions as the first two. For most accounts, two variants at a time is the realistic limit.

ABFinal Editorial · Formulas checked · Methodology