The Quick RMD Percentage Shortcut
Mental shortcut: your RMD percentage at age 73 is approximately 3.77% (about 1/26.5) of your prior-year balance. At age 80 it is approximately 5% (about 1/20). At age 90 it is approximately 8.2% (about 1/12). Use these benchmarks to quickly estimate RMD amounts without looking up the table.
Quick RMD percentage shortcuts by age
| Age | Quick Percentage | On $500K | On $1M | On $2M |
|---|---|---|---|---|
| 73 | ~3.8% | ~$19,000 | ~$38,000 | ~$76,000 |
| 78 | ~4.5% | ~$22,500 | ~$45,000 | ~$90,000 |
| 80 | ~5.0% | ~$25,000 | ~$50,000 | ~$100,000 |
| 85 | ~6.3% | ~$31,500 | ~$63,000 | ~$126,000 |
| 90 | ~8.2% | ~$41,000 | ~$82,000 | ~$164,000 |
The QCD Tax Savings Shortcut
Quick QCD calculation: multiply the QCD amount by your marginal tax rate to estimate immediate federal tax savings. Example: $20,000 QCD at 22% marginal rate saves approximately $4,400 in federal taxes. Add state tax rate for total savings. This quick calculation lets you instantly assess the value of any QCD compared to a cash donation.
At 22% federal bracket: every $1,000 QCD saves approximately $220 in federal taxes. At 24%: $240 per $1,000. At 32%: $320 per $1,000. Use these benchmarks to quickly calculate the tax benefit of any charitable intent directed through a QCD vs. a post-tax cash donation.
Quick RMD mental math tools
| Decision Tool | Quick Formula | Example |
|---|---|---|
| RMD estimate | Balance x RMD% for age | $800K x 4.55% (age 78) = ~$36,400 |
| QCD savings | QCD amount x marginal rate | $15K QCD x 22% = $3,300 saved |
| IRMAA threshold check | Is MAGI above $106K single? | RMD + SS + other > $106K = likely IRMAA |
| Roth conversion room | 22% ceiling minus current income | $100,525 - $65,000 = $35,525 conversion room |
The IRMAA Threshold Quick Check
Simple IRMAA screening question: will your total MAGI (Social Security + other income + RMD) exceed approximately $106,000 (single) or $212,000 (married)? If yes IRMAA surcharges apply. Quick math: Social Security $24K + pension $40K + RMD $40K = $104K — just below IRMAA threshold. A $10,000 QCD would keep you safely below.
- RMD estimate: balance x 3.8% (age 73) or 5% (age 80) for quick mental math
- QCD savings: QCD amount x marginal rate = annual federal tax savings
- IRMAA check: SS + other income + RMD above $106K single = IRMAA applies
- Roth conversion room: 22% bracket ceiling ($100,525 single) minus taxable income = available room
Verify Your Mental Math With the Calculator
Enter your exact balance and age to confirm your RMD estimate and see the precise IRS table calculation.