Excel to Python: A Transition Guide | Finance Train

Excel to Python: A Transition Guide

December 24, 2025

3 min read

Excel to Python: A Transition Guide

If you are comfortable with Excel, you are already halfway to learning Python for data analysis. This guide shows you how your existing skills translate.

Why Make the Switch?

Excel is great, but Python offers:

Handle millions of rows (Excel struggles past 100K)
Automate repetitive tasks
Reproducible analysis
Advanced ML and visualization
Free and runs everywhere

The Pandas Library

Pandas is Python's answer to Excel. A DataFrame is essentially a spreadsheet.

1import pandas as pd
2
3# Read Excel file
4df =

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Excel	Python
Scroll through sheet	`df.head()` - first 5 rows
Ctrl+End	`df.shape` - (rows, columns)
Look at columns	`df.columns`

Excel	Python
Click column A	`df['A']` or `df.A`
Select A and B	`df[['A', 'B']]`
Row 5	`df.iloc[4]` (0-indexed)
A1:B10	`df.loc[0:9, ['A', 'B']]`

Excel	Python
Filter > Greater than 100	`df[df['Sales'] > 100]`
Filter > Text contains "NY"	`df[df['City'].str.contains('NY')]`
Multiple conditions	`df[(df['Sales'] > 100) & (df['Region'] == 'East')]`

Excel	Python
=SUM(A:A)	`df['A'].sum()`
=AVERAGE(A:A)	`df['A'].mean()`
=MAX(A:A)	`df['A'].max()`
=COUNT(A:A)	`df['A'].count()`
=COUNTIF(A:A, ">100")	`(df['A'] > 100).sum()`

df['Total'] = df['Price'] * df['Quantity']

result = pd.merge(df1, df2, on='ID', how='left')

1import pandas as pd
2
3# Load data
4df = pd.read_excel('sales.xlsx')
5
6# Quick overview
7print(df.head())
8print(df.describe())
9
10# Filter to 2024
11df_2024 = df[df['Year'] == 2024]
12
13# Sales by region
14region_sales = df_2024.groupby('Region')['Revenue'].sum()
15print(region_sales)
16
17# Top 10 customers
18top_customers = df_2024.groupby('Customer')['Revenue'].sum().nlargest(10)
19print(top_customers)
20
21# Add profit margin column
22df_2024['Margin'] = (df_2024['Revenue'] - df_2024['Cost']) / df_2024['Revenue']
23
24# Save results
25df_2024.to_excel('analysis_results.xlsx', index=False)
26

python

Excel to Python: A Transition Guide

Excel to Python: A Transition Guide

Why Make the Switch?

The Pandas Library

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Common Operations: Excel vs Python

Viewing Data

Selecting Data

Filtering

Formulas to Functions

Creating New Columns

VLOOKUP → merge()

Pivot Tables

Group By (Subtotals)

Complete Example

Tips for Transitioning

Next Steps