When to choose this
Exact behavior
- Choice fields (multi-select) — checkbox list, tags, dual listbox, etc.
- Normalizes both sides to unique string sets (drops null/empty entries).
- Sorts and compares — order does not matter.
- Blank answers never match (fail-closed, same as equality operators).
- Non-empty expected set required.
- Selecting
{A,B}matches expected{B,A};{A,B,C}does not.
Which field types
Blank / unanswered answers
Never matches. Empty array[] is blank. Use Is empty.
Configure in Studio
1
Open a rule
Logic → Rules, or Branch / Add condition on a field.
2
Pick multi-select field
Checkbox list, tags, flex checklist, etc.
3
Choose Equals set
Set operators appear for choice family.
4
Select exact option chips
Every option that must be selected — and only those.
5
Add Then actions
Show blocks, Calculate bundle pricing.
6
Test exact, superset, subset on Fill
Worked examples
Bundle SKU exactly
When Add-ons equals setSelecting Hosting+SSL only does not match; adding Support breaks match.Hosting, SSL, Backups→ Then Show blocksBundle discount applied
Compliance pair only
When Data processing equals setEU residency, DPA signed→ Then Jump to pageEnterprise onboarding
Quiz multi-answer exact
When Correct topics equals set Safety, Ethics → Then full credit message
Tags exact campaign
When Tags equals set Campaign-2026 → Then campaign-specific thank you
Single-tag set works — equivalent to exact single selection on multi field.
Test on fill
1
Select exactly the set
Rule on.
2
Add extra option
Rule off.
3
Remove one required option
Rule off.
4
Reorder selections
Still on — order ignored.
5
Nothing selected
Rule off.
Common mistakes
- Using Equals set when extras are OK — use Includes every of or Contains.
- Using on single radio — Equals is simpler.
- Expecting blank to match empty set — blank never matches equality/set ops.
Troubleshooting
Almost matches but fails
Almost matches but fails
One extra or missing chip — compare selected values to rule chips in submission preview.
Operator feels too strict
Operator feels too strict
Switch to Includes every of if extras allowed, or Is any of for OR logic.
Single vs multi field
Single vs multi field
Single-select stores one value — set compare still works as one-element set.
Duplicate selections
Duplicate selections
Engine deduplicates via
array_unique — duplicates in UI should not matter.