🌐 Try it now: listcomparator.com
Ever been faced with two (or more) massive lists and the daunting task of finding what’s changed?
Manually comparing spreadsheets or text files is tedious, error-prone, and a huge waste of time.
That’s why I built listcomparator.com — a free, browser-based tool that makes list comparison and data cleanup effortless.
💡 Privacy First: Your data never leaves your computer. Everything runs locally in your browser.
⚙️ Powerful Features at Your Fingertips
Our comparator is packed with capabilities that give you total control over your data:
Multi-List Comparison
Go beyond just two lists — compare up to four lists simultaneously to find common entries or create a unified master list.Intuitive Comparison Modes
For two lists, choose from five clear options such as “In Both (A ∩ B)” or “Only in B (B − A)”.
For three or more lists, use Intersection (In ALL lists) or Union (All distinct items) for quick, broad insights.
🧹 Advanced Data Cleaning
Before comparing, clean your data with a click:
- Trim whitespace
- Remove empty or duplicate lines
- Perform Find & Replace (supports Regex and “Apply to All Lists”)
These options make it easy to standardize or transform entries across multiple lists at once.
📁 Flexible Data Input
Simply paste your lists or upload files (.txt, .csv).
If you upload a CSV, the tool intelligently lets you choose the column to compare — perfect for contact lists or data exports.
📊 Rich Results Display
For two-list comparisons, you’ll see:
- A Venn diagram giving an instant visual summary
- A color-coded Diff View highlighting added and removed lines
👥 Who Is It For?
This tool is built for anyone who handles text or data regularly:
- Marketers: Clean email lists, find new vs. unsubscribed users, or merge contacts from different campaigns.
- Data Analysts: Reconcile datasets, spot discrepancies, or identify common records across multiple sources.
- Developers: Compare configuration files, logs, or feature lists between versions.
- Everyone: Manage product inventories, guest lists, contacts — any text-based dataset.
🚀 Try it now: List Comparator
Created by S. Bozich — privacy-friendly, open-source, and built with ❤️ for the web.