These RMD calculators only work if you include all of your traditional IRA accounts or 401K accounts. I think it is a good idea to consolidate all of your 401Ks and traditional IRAs into a single traditional IRA under a single IRA custodian, like Vanguard. Then the custodian will tell you what your RMD is every year. You don't want to make an RMD mistake.

Ira
 

I am pretty sure that your RMD is not based on 100 years old

Here is the IRS Required Minimum Distribution worksheet and chart for each age.

It calculated to age 115 and older.

https://www.irs.gov/pub/irs-tege/uniform_rmd_wksht.pdf