Postman API has a rate limit of sixty(60) request per minute. This means that a user can make a maximum of 60 requests per minute to any of the endpoints. The API rate limits are applied at a per-key basis in unit time.
When a user hit the rate maximum limit, the user will receive a response similar to the following JSON, with a status code of 429 Too Many Requests.
"message": "Rate Limit exceeded. Please retry at 1465452702843"
When a user receives a 503 response from our servers, it implies that we have hit an unexpected spike in API access traffic and would usually be operational within the next 5 minutes. If the outage persists, the user should contact us.
"name": "503 service unavailable",
"message": "The server is currently not available (because it is overloaded or down for maintenance) Generally this is a temporary state"