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- 🧼 The 3-Minute Fix for Dirty Column Names
🧼 The 3-Minute Fix for Dirty Column Names
Clean up your headers. Write cleaner code. Save time.

Inconsistent column names slow everyone down.
You’ve seen this mess before:
"First Name"
"first_name"
"firstName"
Different formats. Same meaning. But every time, you have to fix it manually.
Let’s fix that — fast.
✅ 3 Fast Ways to Clean Column Names
1. The One-Liner (Pandas)
df.columns = df.columns.str.lower().str.replace(' ', '_')
Lowercases everything
Replaces spaces with underscores
Works in one line — no imports
2. Pyjanitor (Easiest Option)
import janitor
df = df.clean_names()
Automatically handles casing, spaces, and special characters
Ideal for quick cleaning in messy datasets
3. Regex Power (Custom Control)
import re
df.columns = [re.sub(r'\W+', '_', col).lower() for col in df.columns]
Converts symbols to underscores
Keeps things lowercase
Useful when headers are extra messy
🚀 Why This Matters
Less time fixing headers = more time analyzing
Cleaner names = easier to write functions
Standardized columns = fewer bugs in joins & merges
This fix might seem small. But it compounds over time. If you’re cleaning data daily, this saves hours each month.
💡 Pro Tip
Use these techniques inside a data loading function. That way, your columns are always clean — automatically.
Example:
def load_and_clean(path):
df = pd.read_csv(path)
df.columns = df.columns.str.lower().str.replace(' ', '_')
return df
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