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From idea to rollout, in one tool.Product overview

Prepare

Decide

Roll out

Scale

Visual editorBuild the variant without a developer, with the assistant.Test plan and durationDuration calculated before the first visitor.IdeasEach idea estimated from your past tests.Metrics and marginNo-code goals, margin calculated from your orders.
ReportsA one-sentence verdict, with revenue and margin in euros.Session recordings and click mapsSee what visitors do with each variant.GuardrailsA test that breaks something stops on its own.
RolloutsStep by step, with automatic rollback.PersonalizationAn experience for one audience, measured against a holdout.Feature flagsTurn a feature on by rule, and off in one click.
Learnings libraryThe effects of your finished tests, on one scale.Installation and integrationsTwo lines of code, in the browser or on the server.Team and governanceRoles, launch approvals, and an audit log.
Explore the demo Pricing
The rules behind every verdict, set before launch.The full method

The method, step by step

How Probant decidesThe peeking trapThe winner’s curseThe statistics engineGlossaryVerify a report
MethodThe winner’s curseWhy the reported gain is too good, on average.See the correction
Revenue per visitor · Free shipping progress bar
Measured lift+6.0%
After correction+4.9%
+€125,700per month after correction, instead of +€153,300

Corrected using the demo store’s 48 finished tests.

Rerun the simulation with your own number of tests and duration.A/A simulator
By site area and by team.All use cases

You are…

Know what pays off, without a statistician.

The features that matter to you:

ReportsA one-sentence verdict, with revenue and margin in euros.Metrics and marginNo-code goals, margin calculated from your orders.Visual editorBuild the variant without a developer, with the assistant.See the use case
Cart · demo storeFree shipping progress barConclusive. Proven gain+€125,700 per month · revenue per visitor +6.0%, range +2.2% to +10.0%

Computed by the engine on a demo test.

By site areaCart and shippingProduct pageCheckoutMobile navigationCategory pages
Explore the demo
Blog, docs, and tools.All resources
A/A simulatorSee for yourself what peeking costs.Why checking a test every day produces false winners.Run the simulator
BlogMethod, measurement, and lessons learned.
Nov 12What is an A/B test? Definition, steps, and an exampleNov 7Measure margin, not just revenueNov 7The winner’s curse: why the announced gain falls short
All articles
Duration calculatorHow many days it takes to detect the effect you want.DocumentationInstall the script, handle consent, send events.Video tutorialsInstall, launch a test, and read a report, on video.ComparisonsProbant vs. other tools, with sources.AB TastyKameleoonVWOOptimizelyAdobe TargetDynamic Yield+11 more
ChangelogWhat changed in Probant, by date.Case study formatContext, test, result, and decision, on the demo store.Migrate to ProbantImport your AB Tasty, VWO, or Kameleoon history, recalculated by Probant.
Articles, docs, and calculators, free to use.
One fixed monthly price, no overage charges.See pricing

How many visitors do you test each month?

A tested visitor is each unique visitor who sees a test or a rollout during the month. It’s the only thing that sets the price.

Billing
Your planEssential€590/monthor €5,900 per yearFor a store that tests continuously, down to revenue per visitor.
  • Up to 250,000 tested visitors per month
  • All features, unlimited tests within your volume
  • No overage charges
Choose Essential
Your bill never goes over your plan. Once you reach the volume, running tests keep going.Billing questions

Probant exists so that every test tells the truth.

An A/B test answers one question: does the variant earn more? Probant gives the answer in one sentence, with its range and its amount in euros, revenue and margin shown separately. When the data is not enough yet, the report says so.

Four rules the product applies to every test.

They shape what you read in every report, from the test plan to the rollout.

  • A verdict in one sentence.

    The report opens with the conclusion, in plain language, with the range of the effect. The checks are listed alongside for anyone who wants to verify. You don’t need to be a statistician to decide.

  • Margin, in euros.

    A variant can raise revenue and cut into margin, for example by offering free shipping. Probant puts a monthly euro figure on both revenue and margin, after product costs, discounts, and shipping, each with its range. When the margin range includes zero, the report says so.

  • Checkpoints set in advance.

    Checkpoints are set before launch. Across 1,000 simulated A/A tests, comparing two identical versions, checking every day declares a difference in 22% of cases; the planned checkpoints, in 6%.

    The peeking trap

  • Uncertainty, always shown.

    Every effect comes with its range, and the reported gain is corrected for the winner’s curse. “No detectable effect” does not mean “no effect”: the report says what it would take to decide.

    The winner’s curse

An engine checked against reference values.

Each formula in the engine comes with its published source and an automated check against reference values. The differences, ranges, and durations shown in the demo and on this site are computed by the engine from raw data.

The statistics engine: the methods, their sources, and how they are checked.

What the engine computes

  • Relative B / A effects on a proportion or a mean: difference test, Fieller confidence interval
  • Power: sample size, minimum detectable effect, duration in days
  • Sample ratio mismatch (SRM) check
  • CUPED variance reduction
  • Always-valid intervals (mSPRT) and O’Brien-Fleming boundaries
  • Multiple comparisons: Holm, Bonferroni
  • Winner’s curse correction by Bayesian shrinkage

Learn more.

How Probant decidesHow a test reaches its verdict, from locked plan to result.Read the method Security and GDPRDatabase and compute in Amsterdam, with Scaleway, consent first.Read the Security page Press kitLogo, colors, and typography.Open the press kit ContactOne address for every request.See how to reach us

Who makes Probant.

Probant is published by Félix Boittin, sole proprietor (entrepreneur individuel, EI), trading as Clivio. Félix Boittin founded Probant.

The company

Publisher
Félix Boittin, sole proprietor (entrepreneur individuel, EI), trading as Clivio
Registration
SIREN 894 584 770 · SIRET 894 584 770 00016
Registered office
10 rue des Aqueducs, 94250 Gentilly
Team
Félix Boittin founded Probant.
Response time
within 48 hours

Conclusive Or not yet…

Create your workspace, or explore the demo first with data from a fictional store.

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  • Open demo, no sign-up
  • Free to start, no overage charges
  • Database and compute in Amsterdam, with Scaleway