Rate Limits

A rate limit is the number of API calls that can be made within a given time window. Actions such as rapidly updating configuration settings, aggressive polling, or making highly concurrent API calls may result in your account being rate limited.

All API requests are subject to rate limits. Real-time rate limit usage statistics are described in headers that are included with most API responses. When requests get blocked, responses with HTTP status -32(Too Many Requests) are returned.

Each API endpoint, or each group of API endpoints has a rate limit policy.

Messaging API Rate Limits

Endpoint	Rate Limit Policy
POST https://api.antgst.com/sms/txt/2/	200 rps, per account
POST https://api.antgst.com/sms/hlr/	60 rps, per account
POST https://api.antgst.com/call	200 rps, per account
POST https://api.antgst.com/sms/txt/3/	60 rps, per account
POST https://api.antgst.com/user/account/	200 rps, per account

Most endpoints are rate limited to 200 rps (requests per second) per account.

OTP messaging API endpoints' usage statistics are measured separately, but you should not use both of them at a high rate at the same time. The /sms/txt/3/send/json​ endpoint can accept requests at a rapid rate of 200 rps, while ANT submits these messages to the channel API at a lower rate of 60 rps.