Kissmetrics

Kissmetrics Tracking API (Beacon)

Event ingest surface. Three query-string endpoints record an event (/e), set person properties (/s) and irreversibly alias two identities to one person (/a), accepting GET or POST with the product key in `_k`, the person identity in `_p` and arbitrary additional keys as person properties. It powers the hosted JavaScript snippet, the first-party Ruby, PHP, Python, iOS and Android libraries, and the 1x1 pixel beacon used for email and ad impression tracking. By design it answers 200 OK with a 1x1 GIF to every request, valid or not, so a 200 is not evidence an event was accepted. This entry replaces the former Kissmetrics Data Out API entry, whose only documentation host, oldsupport.kissmetrics.com, no longer resolves (probed 2026-08-13).

GitHub

Documentation

📖
Documentation
https://support.kissmetrics.io/reference/api-specifications-1
📖
GettingStarted
https://support.kissmetrics.io/docs/installing-the-javascript-library-quickstart

Other Resources

🔗
Beacon API
https://support.kissmetrics.io/reference/beacon-api-1
🔗
AgentSkill
https://raw.githubusercontent.com/api-evangelist/kissmetrics/refs/heads/main/skills/kissmetrics-km-installer.md
🔗
SDKs
https://raw.githubusercontent.com/api-evangelist/kissmetrics/refs/heads/main/packages/kissmetrics-packages.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: kissmetrics:tracking-api
name: Kissmetrics Tracking API (Beacon)
description: Event ingest surface. Three query-string endpoints record an event (/e), set person properties
  (/s) and irreversibly alias two identities to one person (/a), accepting GET or POST with the product
  key in `_k`, the person identity in `_p` and arbitrary additional keys as person properties. It powers
  the hosted JavaScript snippet, the first-party Ruby, PHP, Python, iOS and Android libraries, and the
  1x1 pixel beacon used for email and ad impression tracking. By design it answers 200 OK with a 1x1 GIF
  to every request, valid or not, so a 200 is not evidence an event was accepted. This entry replaces
  the former Kissmetrics Data Out API entry, whose only documentation host, oldsupport.kissmetrics.com,
  no longer resolves (probed 2026-08-13).
humanURL: https://support.kissmetrics.io/reference/api-specifications-1
baseURL: https://trk.kissmetrics.io
tags:
- Analytics
- Event Tracking
- Data Ingest
- Identity Resolution
properties:
- type: Documentation
  url: https://support.kissmetrics.io/reference/api-specifications-1
- type: Beacon API
  url: https://support.kissmetrics.io/reference/beacon-api-1
- type: GettingStarted
  url: https://support.kissmetrics.io/docs/installing-the-javascript-library-quickstart
- type: AgentSkill
  url: skills/kissmetrics-km-installer.md
- type: SDKs
  url: packages/kissmetrics-packages.yml