# Custom events and properties

> Track signups, purchases and other custom events with privatus.track(), HTML attributes or your server, plus naming rules, limits and how events count as usage.

A **custom event** is something that happens on a page: a signup, a
purchase, a video play. Events have a name and optional properties.

```js
privatus.track('Signup', { plan: 'pro', seats: 3 })
```

Events appear in the Conversions panel on the Overview and in the
[Events explorer](/docs/dashboard/events), and can become
[goals](/docs/features/goals) and [funnel](/docs/features/funnels) steps.

Three ways to send them:

1. **JavaScript:** `privatus.track()` ([API](/docs/tracker/javascript-api)).
2. **HTML attributes, no code:** `data-privatus-event="Signup"`
   ([HTML attributes](/docs/events/html-attributes)).
3. **From your server:** the [server-side ingest API](/docs/server-side).

The [`auto` module](/docs/tracker/modules#auto-automatic-events) tracks
outbound links, downloads, forms and 404s for you.

## Naming

- Up to **120 characters**, any language and script. Longer names are cut.
- Leading and trailing spaces are trimmed and Unicode is normalised (NFC),
  so `Café` typed two different ways is one event.
- Case is kept for display. Pick one style and stick to it:
  `Signup` and `signup` are stored as written. You can merge names later in
  **Site settings → Events & properties**.
- Name the action, not the element: `Signup`, `Checkout started`,
  `Invoice downloaded`, rather than `Blue button click`.
- Don't put variable data in names (`Viewed product 123`). Use a
  property.

## Limits

| Limit | Value |
|---|---|
| Event name | 120 characters |
| Properties per event | 30 (extra ones are dropped) |
| Property key | 64 characters, `a-z`, `0-9`, `_` |
| String value | 500 characters |
| Array value | up to 30 strings |
| Property keys per site | 10 on Free, unlimited on paid plans |
| Request body | 32 KB |

## Usage

Every custom event counts as one event toward your monthly allowance, like
a pageview. Engagement pings, Web Vitals, click-map hits and bots don't
count. See [What counts as an event](/docs/billing/usage).

## Managing events

In **Site settings → Events & properties** you can rename events (history
is rewritten at query time), merge several names into one, hide events,
and delete an event including its history. See
[Events explorer](/docs/dashboard/events).