Property Explorer

The Property Explorer (sidebar Explore → Property Explorer) shows every property key your applications attach to events, with cardinality stats — how many distinct values each property has taken. It’s the answer to “what details are we collecting along with our events, and which of them are well-behaved versus high-cardinality outliers?”

Plan note: Property Aggregation is enabled on Trial and Pro+ plans. Starter tenants see a plan-upgrade prompt instead. (Trial gets it during the 21-day window so customers can preview the feature; Starter is the gated step before Pro.)

When to use it

You inherited a project and want to see what custom properties the SDK is sending.
A teammate asked “do we track which export format users pick?” and you need to find out.
Auditing for properties that shouldn’t be there — names that look like personally-identifying information, debug flags that snuck through to production, etc.
Spotting high-cardinality properties (those with many distinct values) — usually a sign of property misuse you’ll want to fix.

Filters

A simpler filter strip than the Event Explorer — Property Explorer focuses on cross-event property discovery, so the event-specific narrowing controls are hidden:

Product — limit to one application.
Time range with presets and custom selection.

That’s it. There’s no Source version, no Group by, no Category / Event name, no Compare. The view is intentionally broad.

Sections

Property stats cards

Four cards summarizing the window:

Total Properties — total distinct property keys observed.
High Cardinality — count of properties flagged as high-cardinality (too many distinct values). Each high-cardinality property is also visually marked in the table below.
Avg Distinct Values — average number of distinct values per property. A lower number means most of your properties are well-behaved enums; a higher number suggests free-form data.
Max Distinct Values — the highest distinct-value count of any single property, plus the property name. Often the first thing to investigate when this number looks suspicious.

Property keys overview table

A sortable table with one row per property key. Columns include the property key, total event count, distinct value count, and a high-cardinality flag. Each row expands to reveal the events that use the property, with quick links to drill into Event Detail filtered by that property.

Data freshness

Property Explorer reads live event data on each request — it’s one of the few surfaces in the Explore section that doesn’t wait for the 15-minute aggregator. New properties appear as soon as the SDK flushes a batch and the API accepts it.

Property limits

Beacon enforces hard limits on property data to keep query performance predictable:

Maximum 20 properties per event.
Property key max length: 64 characters.
Property value max length: 256 characters.

Events that exceed these limits are rejected at ingestion. If you see properties missing that you expected, check Invalid Events for these specific error codes:

PROPERTIES_TOO_MANY_KEYS — the event had more than 20 properties.
PROPERTIES_KEY_TOO_LONG — at least one property key exceeded 64 characters.
PROPERTIES_VALUE_TOO_LONG — at least one property value exceeded 256 characters.

Common questions

A property I’m sending isn’t showing up.

It exceeds limits. Check Invalid Events for the property-specific rejection codes above.
You’re outside the time window. A property only used in older releases won’t appear if your filter is set to “Last 7 days.”

One property key is flagged high-cardinality. That means it took on a lot of distinct values — often a sign that you’re sending something like a user-generated string, a UUID, or a timestamp as a property value. High cardinality is fine for some use cases (audit trails) but expensive for others (charting, segmentation). Consider whether the value belongs in the event’s actor_id or as a hashed/bucketed property instead.

I’m on the Starter plan and Property Explorer is greyed out. Property Aggregation activates at Pro. Upgrade to access it, or use Event Explorer — that surface is available on every paid plan.

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