Flo Docs
A/B Testing

Traffic Split

Creator plan required

While a test is in Draft, running, or paused, adjust splits in the builder right panel under Split test → Traffic.

Default split

New tests with two variants start 50% / 50%. Flo uses integer percents that always sum to 100.

When you add a variant, splits rebalance evenly (for three variants: 34%, 33%, 33% style distribution).

Change percentages

  1. Open Split test panel

    Click the Draft / Live / Paused pill in the header if the panel is closed.

  2. Drag sliders or type values

    Each variant row shows its traffic %. Adjust until the total bar reads 100%.

  3. Wait for auto-save

    Copy in the panel: Changes save automatically.

Single-variant edge case

With only one variant, the UI shows 100% traffic and explains you need another variant to split traffic.

When splits apply

Test statusVisitors
DraftEveryone sees the normal live page — splits are not active
RunningNew visitors assigned by split; returning visitors keep their persisted variant (see below)
PausedAssignment pauses with the test
CompletedTraffic returns to the live page only

Sticky assignment

Flo stores your visitor's variant in ab_test_assignments on first assignment. If you change traffic from 50/50 to 70/30, returning visitors stay on the variant they were first shown — only new visitors follow the updated split.

Each visitor gets a stable anonymous flo_vid cookie before their first assignment. When analytics consent is off, edge routing on your published myflo.link/{username} page sets the cookie before the first view. When consent is on, visitors Accept the banner first; Flo then records the variant view used in your A/B report (including ab_variant_id for running tests).

Rendering vs conversion credit

Sticky assignment controls which variant a visitor sees while a test is running. When they purchase or subscribe later, Flo credits the test only if that exposure was within the last 30 days — not months afterward.

What's next?