Dicno LabsMortgage rates
Estimate rate lock or extension costs and compare them with payment impact.
Free mortgage tool
A rate lock cost calculator helps estimate the cost of locking or extending a mortgage rate and compare that cost with potential payment differences. Rate lock policies vary by lender, loan type, and market conditions.
This tool estimates lock cost from the loan amount and lock cost percentage, then compares payments at two rates to show monthly payment difference and simple break-even timing.
Use it when discussing lock periods, extensions, and lender pricing, but rely on written lender disclosures for actual terms.
This calculator is for educational and planning purposes only. It is not financial advice, a loan approval, a tax bill, or a lender quote.
Calculator
The estimate updates instantly in your browser as you adjust the inputs.
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Formula
Lock cost equals loan amount multiplied by lock cost percentage plus fixed lock fee. Payment difference compares the two mortgage payments. Break-even divides lock cost by monthly savings when the locked rate is lower.
A 0.25% lock cost on a $350,000 loan is $875. If the locked rate saves $55 per month, the simple break-even time is about 16 months.
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Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
Rate Lock Cost Calculator is an educational planning tool. Use the result as a starting point, then compare it with written lender, servicer, tax, or closing documents when available.
HomeLoan Compass
Use HomeLoan Compass when a single estimate turns into a multi-loan decision.