Financial Calculator User Guide
RATE · Rate conversion
Choose an instruction to see the matching keys and values. Practice separately in the real calculator.
Open financial calculator ↗Worked examples
Know the mode controls
APR is nominal; EAR includes compounding. Supported C/Y values are 1, 2, 4, 12 and 365. Enter 12 for 12%, not 0.12, and solve either APR or EAR.
Review these controls before choosing a case. Keystroke steps show menus opening, selection and closure.
EAR · Open lesson
EAR · Effective annual rate — Enter a percentage or SOLVE from APR and C/Y; includes annual compounding.
1. Organize the inputs
Convert nominal and effective annual rates
At APR=12% and monthly compounding C/Y=12, what is EAR? Reverse the same EAR to recover APR.
| Variable | Input | Action |
|---|---|---|
| APR | 12 | EXE |
| EAR | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–5
3. Show answer and interpretation
%
EAR includes intra-year compounding, approximately 12.6825%; APR is nominal. The inverse uses full-precision EAR to avoid rounding error.
4. Avoid these mistakes
- Enter 12, not 0.12. Supported C/Y values are 1, 2, 4, 12 and 365. P/Y is not compounding frequency.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗APR · Open lesson
APR · Nominal annual rate — Enter a percentage (12 for 12%) or SOLVE from EAR and C/Y.
1. Organize the inputs
Convert nominal and effective annual rates
At APR=12% and monthly compounding C/Y=12, what is EAR? Reverse the same EAR to recover APR.
| Variable | Input | Action |
|---|---|---|
| EAR | 12.682503013 | EXE |
| APR | Unknown | Select → SOLVE |
2. Follow the keystrokes
Steps 1–5
3. Show answer and interpretation
%
EAR includes intra-year compounding, approximately 12.6825%; APR is nominal. The inverse uses full-precision EAR to avoid rounding error.
4. Avoid these mistakes
- Enter 12, not 0.12. Supported C/Y values are 1, 2, 4, 12 and 365. P/Y is not compounding frequency.
- Finish input with EXE before solving. Clear or changed inputs/settings invalidate earlier results; calculate again.
5. Practice it yourself
The link opens a separate calculator tab. It does not fill, clear or change your calculator's inputs; follow the settings and rows above.
Practice in the financial calculator (new tab) ↗Supported results and operating manual
Targets across the lessons: EAR · APR
RATE · Operating manual
- Enter nominal APR (12 means 12%), set annual compounding C/Y in Settings, then select EAR and SOLVE.
- For the inverse, enter EAR and solve APR.
Keys and settings
Keys and workflow
- ↑↓ selects the active row. The highlighted row is the variable you are editing.
- Enter a number or expression (500*6 or 10000*(1.05)^10), then EXE to evaluate, store and advance. Dates use date input instead of expressions.
- SOLVE calculates the selected unknown/output from the other known values. MATH uses EXE only.
- CLR clears the draft while editing; otherwise it clears only the selected stored variable. Backspace recalls a stored value and deletes its last character, then EXE stores the change. Escape cancels a draft and restores the original value. After EXE advances, select the field you want to change. Clearing a stored input invalidates dependent results. Selecting a read-only result or history row leaves it untouched; settings and MATH history are preserved. MENU offers current-mode clear and calculator reset.
Settings: P/Y is payments per year; C/Y is compounding per year. BEGIN/END selects beginning/end-of-period payments for TVM and AMRT. N counts payment periods, not years. Enter 5 for 5%.
MENU → Fill Example provides working inputs for the current mode. N/A or an error means the inputs/settings do not support a valid result; check the highlighted field and domain restrictions.
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