Loan Calculator

Purpose

This repository contains Python scripts for personal finance loan calculators.

Contents

• Loan Info.csv
• Loan_Calc_FNs.py
• Loan_Calc_Iterate.py

Instructions:

Ensure the .venv is activated in your terminal before running the script.

• Activate Virtual Env via "..venv\Scripts\Activate.ps1" in terminal

1. Input your loan information in 'Loan Info.csv' in the same directory as this script.
2. Adjust user inputs below as needed (monthly payment, date range).
3. Run the script to generate amortization tables and summary reports.
   • View Export Tables in the 'Export' folder created in the script directory.

Export Contents

• Amortization Table.csv - Month-by-month breakdown of payments, interest, and remaining balance for each loan
• Loan Order Iterations.csv - Different prioritization strategies tested
• Monthly vs Total Cost.csv - Analysis of different monthly payment amounts
• Summary.csv - Total interest and payments per loan
• Weight Iterations.csv - Results from testing different weighting strategies

Example: Monthly vs Total Cost.csv

Compares different monthly payment amounts and their impact on total interest:

Monthly	Interest Total	Payments Total	Months
$1,400	$11,857	$79,482	57
$1,600	$9,497	$77,122	49
$1,800	$7,915	$75,539	42
$2,000	$6,819	$74,443	38
$2,200	$6,011	$73,636	34

Higher monthly payments = less interest paid and faster payoff

Example: Summary.csv

Shows total interest paid and total payments for each loan at the user input monthly payment:

Category	Loan01	Loan02	Loan03	Loan04	Loan05	Loan06	Loan07	Loan08	Sum
Interest	$468	$2,698	$700	$430	$532	$951	$543	$496	$6,819
Payment	$4,261	$26,106	$5,740	$5,291	$5,883	$15,263	$5,866	$6,032	$74,443

Example: Amortization Table.csv

First few rows showing monthly payment breakdown:

Date	Total Payment	Loan02 Payment	Loan02 Interest	Loan02 Remaining	Loan01 Payment	Loan01 Interest	...
2024-01-01	$2,000	$0	-	$23,408	$0	-	...
2024-02-01	$2,000	$1,145	$219	$22,482	$85	$24	...
2024-03-01	$2,000	$1,145	$211	$21,547	$85	$24	...

Example: Weight Iterations.csv

Tests different prioritization strategies (rate weight vs. total balance weight):

Rate Weight	Total Weight	Interest Total	Payments Total	Months
0.0	1.0	$8,845	$76,469	39
0.25	0.75	$8,463	$76,088	39
0.5	0.5	$7,487	$75,112	38
0.75	0.25	$6,965	$74,589	38
1.0	0.0	$6,819	$74,443	38

Higher rate weight (1.0) = prioritize high-interest loans first = lowest total interest

Example: Loan Order Iterations.csv

Shows the payoff order for each weighting strategy tested:

Strategy	1st	2nd	3rd	4th	5th	6th	7th	8th
0	Loan01	Loan04	Loan03	Loan07	Loan05	Loan08	Loan06	Loan02
8	Loan01	Loan03	Loan04	Loan05	Loan02	Loan07	Loan06	Loan08

Different strategies produce different loan payoff orders