Overview
The Savings Withdrawal Calculator helps you estimate how long your current savings will last when making regular withdrawals. It considers compounding interest, withdrawal amounts, and even optional contributions, making it ideal for retirement planning and financial forecasting.
By modeling how your balance decreases over time with interest applied, this tool gives you a realistic projection of your financial longevity.
Formula & Methodology
The calculator uses iterative future value and annuity math to model balance decline:
- Monthly Interest Rate = Annual Rate / 12 / 100
- New Balance Each Month = (Previous Balance + Monthly Contribution) × (1 + r) − Withdrawal
This process continues until the balance reaches zero or the defined number of months is completed.
Examples
- Initial Savings: $100,000
- Withdrawal: $1,000/month
- Interest Rate: 5% annually (≈ 0.4167% monthly)
- Result: Savings last approximately 11 years and 6 months
Use Cases
- Planning retirement withdrawals over time
- Modeling emergency fund depletion
- Simulating withdrawal scenarios with interest gains
- Determining how contributions can extend financial runway
FAQ
Does this tool assume constant interest rates?
Yes, it assumes a fixed annual interest rate compounded monthly. In reality, returns may vary, so use this as a guideline.
Can I model both withdrawals and contributions?
Yes, the calculator allows optional monthly contributions to simulate income or additional deposits.
What happens if my interest is greater than my withdrawal?
Your savings may grow instead of depleting, and the tool will reflect a growing balance over time.
What compounding options are supported?
You can select common options like monthly, quarterly, or annual compounding.