I, and my wife, have multiple IRA, ROTH IRA, Sep IRA, Rollover IRA and 401K accounts. I am 64, my wife is 58. I am planning to retire between 70 and 72. I was wondering how our MRD will be computed and is there is a site or an equation that gives our MRD.
Publication 590 (note my link is to 590b which offers advice on the withdrawal side 590a covers deposits) offers the chart for this. Each year a 70.5 or older person has an RMD, a percent of retirement accounts based on end of prior year balance.
The math is not too tough. The 401(k) is treated as a separate entity. No RMD as long as you work. Then RMDs based on the account balance. All IRAs can be added up, RMD calculated, and the withdrawal made for that amount from any account.
This is the first decade. It's given as a divisor, i.e. Take the balance and divide by the number for the RMD that year. You can see how it grows, the RMD becoming a higher percent as you get older.
Two side notes - play with a spreadsheet, do the math. Project out ten years. If RMDs are likely to push you to a higher bracket, consider using Roth conversions to pull in some income, and "top off" your existing bracket. You'll build up Roth accounts at a lower marginal rate and have access to the money including growth, after five years. Second - the prior advice may fail if either of you wind up in a nursing home. The cost becomes a medical write off and effectively tax free (there's some math to do, cost has to exceed a percentage of income and standard deductions, etc, and then it's all a write off.)