You enter the monthly benefit at one claiming age. The page scales that benefit to the other claiming ages using the early and delayed factors in the tool, so you can compare the monthly amounts. It does not contact the Social Security Administration and it does not read a statement.
If the benefit you type at full retirement age is $2,000 a month, claiming earlier shows a smaller monthly amount and claiming later shows a larger one. The comparison is only as good as the benefit you entered.
This is United States Social Security. It is not the Canada Pension Plan or Old Age Security. Spousal benefits, the earnings test, and taxation of benefits are not calculated.