Refresh tokens have normally a very long expiration times relative to access tokens. Because refresh tokens are more valuable than access tokens they are usually only issued via the OAuth “Authorization Code Grant” flow.

When a token is created using an API flow a "expires_in" can be set to a specific number.

Please find the bellow snippet from the article https://developer.okta.com/authentication-guide/tokens/refreshing-tokens

http --form POST https://{yourOktaDomain}/oauth2/default/v1/token \

accept:application/json \

authorization:'Basic MG9hYmg3M...' \

cache-control:no-cache \

content-type:application/x-www-form-urlencoded \

grant_type=refresh_token \

redirect_uri=http://localhost:8080 \

scope=offline_access \

refresh_token=MIOf-U1zQbyfa3MUfJHhvnUqIut9ClH0xjlDXGJAyqo

If the refresh token is valid, then you get back a new access/refresh token combination:

{

"access_token": "eyJhbGciOiJ[...]K1Sun9bA",

"token_type": "Bearer",

"expires_in": 3600,

"scope": "offline_access",

"refresh_token": "MIOf-U1zQbyfa3MUfJHhvnUqIut9ClH0xjlDXGJAyqo"

}