How to set a participant's preferred language

Use this guide when you need to set or change the default language for a participant's account. This controls the language used for platform notifications.

⚠️ This field is global. default_lang is stored at the environment level. Updating it in one event will cascade to every other event this account is attached to within the same data environment.

What you'll need before starting

What you need	Where to get it
Participant ID, External ID, or email	`GET /api/v2/account/get` or `GET /api/v2/participants/{eventId}/list`
Supported language codes	`GET /api/v2/sessions/getLanguages` — returns the languages configured for the event

Request

Bash

curl -X POST "https://your-event-domain.com/api/v2/account/set" \
  -H "Authorization: Bearer your_api_key_here" \
  -F "event_id=7" \
  -F "id=12345" \
  -F "default_lang=de"

Notes

default_lang accepts an ISO 639-1 two-letter language code (e.g. en, fr, de, es)
The language must be one of the languages configured for the event
You can identify the participant by id, external_id, or email