Signals | Caption Kit Help Center

Before you get started make sure to create an API key in your CaptionKit dashboard and read up on the API authentication.

Signal types

captions:stream:start - Start streaming captions
captions:stream:stop - Stop streaming captions
captions:stream:clear - Clear caption text
captions:pending:on - Turn on "Starting soon" message
captions:pending:off - Turn off "Starting soon" message
captions:visibility:hide - Temporarily hide captions
captions:visibility:show - Show captions
language:select - Set transcription language
- This signal requires an additional value={language} parameter. Read further down for details.

Get ready to receive signals

To receive signals in your CaptionKit dashboard, toggle on the 📡 Signals button in the caption controls area.

Sending a signal

Signals can be sent using either a POST or GET request to the following URL:

https://api.captionkit.io/v2/signal

For the below examples, the API_KEY will be included in a query param, but this can also be included in the request headers.

GET /signal

Using curl

curl https://api.captionkit.io/v2/signal?key={API_KEY}&event=captions:stream:start

Using fetch in JS or Node

fetch( 'https://api.captionkit.io/v2/signal?key={API_KEY}&event=captions:stream:start');

POST /signal

Using curl

curl -X POST https://api.captionkit.io/v2/signal?key={API_KEY} -H 'Content-Type: application/json' -d '{"event":"captions:stream:start"}'

Using fetch in JS or Node

fetch('https://api.captionkit.io/v2/signal?key={API_KEY}', { method: 'POST', headers: { 'Content-Type': 'application/json', }, body: JSON.stringify({ event: 'captions:stream:start', }),});

Language selection

When using the language:select signal, you must include a value parameter in the request, with a validlanguage code. For example, to set the language to English, you would use the language code en.

The available language codes are:

en English
en-US English (US)
en-AU English (AU)
en-GB English (GB)
en-NZ English (NZ)
bg Bulgarian
cs Czech
da Danish
nl Dutch
fr French
fr-CA French (Canada)
de German
de-CH German (Switzerland)
el Greek
hi Hindi
hu Hungarian
id Indonesian
it Italian
ja Japanese
ko Korean
lt Lithuanian
ms Malay
no Norwegian
pl Polish
pt Portuguese
pt-BR Portuguese (Brazil)
ro Romanian
ru Russian
es Spanish
es-419 Spanish (Latin America)
sv Swedish
th Thai
tr Turkish
uk Ukrainian
vi Vietnamese
zh Chinese (Mandarin, Simplified)
zh-TW Chinese (Mandarin, Traditional)
zh-HK Chinese (Cantonese, Traditional)

CaptionKit also supports a special multi language code, which is for bilingual English and Spanish speech.

Output only language codes

These languages are only available in the CaptionKit dashboard "translations" selection, but are listed here for reference:

ar Arabic
fa Farsi/Persian
ht Haitian Creole
rw Kinyarwanda
sw Swahili

Requesting new languages

If you don't see your language above, reach out to our support team! We are in the process of adding more languages and will prioritize requested languages first.

Supported languages