Ti84 Calculator

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TI-84 TVM Solver Calculator
Future Value (FV)Present Value (PV)Payment (PMT)Number of Periods (N)
Result:
FV = 0.00
function toggleInputs(){var mode=document.getElementById('solve_for').value;var rows=['row_n','row_pv','row_pmt','row_fv'];for(var i=0;i<rows.length;i++){document.getElementById(rows[i]).style.display='table-row';}if(mode==='n'){document.getElementById('row_n').style.display='none';}else if(mode==='pv'){document.getElementById('row_pv').style.display='none';}else if(mode==='pmt'){document.getElementById('row_pmt').style.display='none';}else if(mode==='fv'){document.getElementById('row_fv').style.display='none';}}function calculateTVM(){var mode=document.getElementById('solve_for').value;var n=parseFloat(document.getElementById('input_n').value);var i_ann=parseFloat(document.getElementById('input_i').value);var pv=parseFloat(document.getElementById('input_pv').value);var pmt=parseFloat(document.getElementById('input_pmt').value);var fv=parseFloat(document.getElementById('input_fv').value);var py=parseFloat(document.getElementById('input_py').value);if(isNaN(i_ann)||isNaN(py)){alert('Please enter valid numeric values for Rate and P/Y');return;}var r=i_ann/100/py;var res=0;var label="";if(mode==='fv'){if(isNaN(n)||isNaN(pv)||isNaN(pmt)){alert('Check N, PV, and PMT');return;}var q=Math.pow(1+r,n);res=-(pv*q+pmt*(q-1)/r);label="FV";}else if(mode==='pv'){if(isNaN(n)||isNaN(fv)||isNaN(pmt)){alert('Check N, FV, and PMT');return;}var q=Math.pow(1+r,n);res=-(fv+pmt*(q-1)/r)/q;label="PV";}else if(mode==='pmt'){if(isNaN(n)||isNaN(pv)||isNaN(fv)){alert('Check N, PV, and FV');return;}var q=Math.pow(1+r,n);res=-(pv*q+fv)/((q-1)/r);label="PMT";}else if(mode==='n'){if(isNaN(pv)||isNaN(fv)||isNaN(pmt)){alert('Check PV, FV, and PMT');return;}if(r===0){res=-(pv+fv)/pmt;}else{res=Math.log((pmt-fv*r)/(pmt+pv*r))/Math.log(1+r);}label="N";}document.getElementById('resultLabel').innerHTML=label;document.getElementById('resultValue').innerHTML=res.toLocaleString(undefined,{minimumFractionDigits:2,maximumFractionDigits:2});if(document.getElementById('show_steps').checked){var summary="TVM Summary:
N = "+n+"
I% = "+i_ann+"
PV = "+pv+"
PMT = "+pmt+"
FV = "+fv+"
P/Y = "+py;document.getElementById('stepsDisplay').innerHTML=summary;document.getElementById('stepsDisplay').style.display='block';}else{document.getElementById('stepsDisplay').style.display='none';}}toggleInputs();

Calculator Use

This TI-84 calculator emulator focuses on the most powerful feature of the physical handheld device: the Time Value of Money (TVM) Solver. Whether you are a student in a finance class or a homeowner calculating mortgage payments, this tool replicates the logic used by Texas Instruments calculators to solve for complex financial variables.

By entering known variables like the interest rate, present value, and payments, you can instantly find the missing piece of your financial puzzle. This is essential for understanding how debt amortizes or how investments grow over time.

N (Number of Periods)
The total number of payment periods (e.g., 360 for a 30-year monthly mortgage).
I% (Annual Interest Rate)
The nominal annual interest rate as a percentage (enter 5 for 5%).
PV (Present Value)
The current value of an investment or the principal amount of a loan.
PMT (Payment)
The amount paid or received in each period.
FV (Future Value)
The value at the end of the term, often 0 for loans that are fully paid off.

How It Works

The TI-84 calculator TVM solver operates on the standard accounting convention: cash inflows are positive and cash outflows are negative. For example, if you receive a loan of $10,000, your PV is +10,000. Because you are making payments back to the bank, your PMT must be entered as a negative number.

The fundamental equation used by the calculator is:

PV(1+i)n + PMT[(1+i)n – 1] / i + FV = 0

Where:

  • i = Interest rate per period (Annual Rate / 100 / Payments per Year)
  • n = Total number of periods
  • PV, PMT, FV = The monetary values described above

TI-84 Calculation Example

Scenario: You want to buy a $300,000 home with a 30-year fixed-rate mortgage at 7% interest. You want to find your monthly payment.

Step-by-step solution:

  1. Set Solve For to PMT.
  2. Input N = 360 (30 years × 12 months).
  3. Input I% = 7.
  4. Input PV = 300000 (The amount you receive from the bank).
  5. Input FV = 0 (The loan will be paid off).
  6. Input P/Y = 12 (Monthly payments).
  7. Click Solve.
  8. Result: PMT = -1,995.91. (The negative sign indicates money leaving your pocket).

Common Questions

Why is my result negative?

In a TI-84 calculator, the sign represents the direction of cash flow. If you "get" money (like a loan), it is positive. If you "give" money (like a payment or deposit), it is negative. For a calculation to work, there must usually be at least one positive and one negative value.

How do I calculate for different compounding?

Adjust the P/Y (Payments per Year) setting. If you are calculating a savings account that compounds quarterly but you make monthly deposits, the TI-84 handles this by adjusting the periodic rate. This emulator assumes P/Y and C/Y are the same for simplicity.

Can this solve for Interest Rate?

Solving for I% requires an iterative numerical method (like the Newton-Raphson method) because the rate cannot be isolated algebraically in the TVM formula. For students, it is often easier to use the physical TI-84 calculator for rate calculations or an online financial solver specifically designed for rate iteration.

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