Excel & Google Sheets columns
Paste two spreadsheet columns to catch mismatched SKUs, IDs, or names before you merge or upload data.
Private list reconciliation
Compare lists online
Paste or import two sources below to find what matches, what changed, and the clean master set — nothing ever leaves your browser.
List 1
Your reference listList 1VSList 2
List 2
The list to reconcileResult
The complete relationship, in one view.
Compare both lists to reveal what stayed, what changed, and the clean master set.
Private by architectureYour lists are reconciled locally and never leave this browser.
Encrypted context · Zero retentionTips for using the list comparison tool
This tool compares two lists of words or numbers and shows every relationship between them. No unnecessary functionality — just list comparison, done well. Operations include:
- Set differences — items unique to List A or List B
- Intersection — items shared by both lists
- Union — every distinct item across both lists
- Symmetric difference — everything that differs between the lists
You can compare lists with or without case sensitivity, trim leading/trailing whitespace, ignore blank lines, and sort results naturally. Use the Copy, Clear, Sort, Split, and Clean buttons on each list if you need to prepare your data first. The tool works on desktops and smartphones.
Private by architecture. All comparisons run locally in your browser using JavaScript — no list data is transmitted to or stored on a server.
What counts as a duplicate?
By default, “Alpha”, “alpha”, and “ alpha ” resolve to the same item. Turn on case sensitivity or turn off trimming to change that behavior.
Can I compare CSV columns or files?
Yes. Open a CSV or paste delimited content, then choose commas, semicolons, tabs, pipes, or auto-detection as the separator.
Does DiffLists save my lists?
No. Comparisons happen in the current browser tab and are not transmitted or persisted by DiffLists.
Can I compare two Excel or Google Sheets columns?
Yes. Copy a column directly from either app and paste it into List 1 or List 2 — no need to save as CSV first. See the Excel and Google Sheets guides below for full walkthroughs.
Is there a limit to how many items I can compare?
There's no hard limit. Everything runs in your browser tab, so very large lists (hundreds of thousands of lines) are fine, though extremely large files may take a moment to process.
What output formats can I copy or download?
Copy any single result panel to your clipboard, download it as a plain text file, or use Export full report to save all five result sets plus match-rate stats as one JSON file.
Does natural sort handle numbers with leading zeros?
Yes. Natural sort compares numeric segments as numbers rather than character by character, so “item-2” sorts before “item-10” and zero-padded codes like “007” stay in the right order.
Can I compare Instagram or other social media follower lists?
Yes. Export your followers and following lists, paste each into a list, and compare to see who doesn't follow back, who's new, and who unfollowed since your last export.
Built for real workflows
One tool, every list-comparison job
Whatever two lists you’re staring at, the same five results apply. Here’s where people put DiffLists to work.
CSV & database exports
Reconcile nightly exports, CRM dumps, or migration reports without writing a VLOOKUP or SQL join.
Instagram & social follower lists
Compare exported follower and following lists to see who unfollowed you, who's new, and who overlaps.
Email & subscriber lists
Check newsletter exports before a send to remove duplicates and confirm unsubscribes went through.
Config & dependency diffing
Paste two dependency lists or config keys to spot what changed between environments or releases.
Inventory & records
Match product catalogs, asset tags, or attendee rosters between two systems that don't talk to each other.
Flexible input, clean output
Works with more than plain lists
DiffLists isn’t limited to tidy one-item-per-line lists. It’s built to handle the messy, real-world data you actually paste in.
- Any delimiter — commas, semicolons, tabs, pipes, or auto-detect, so pasted CSV rows split into items correctly.
- File import — drag in a .txt, .csv, .tsv, or .log export instead of copy-pasting.
- Natural sort — keeps numeric IDs and zero-padded codes in the right order instead of sorting them as plain text.
- Case-sensitive matching— toggle it on when “ABC-1” and “abc-1” need to count as different items.
- Copy or export — grab a single result set, or download a full JSON report with every operation and match-rate stats.
From the blog
Guides for comparing lists the right way
5 min read
How to Compare Two Lists Online (Free & Fast)
Stuck cross-checking two lists by eye? Paste both in and instantly see matches, duplicates, and differences — free, private, no signup required.
5 min read
How to Find Duplicates Between Two Lists
Chasing duplicate entries across two spreadsheets? Find every shared item instantly, plus how to clean duplicates within a single messy list.
7 min read
Compare Two Excel Columns for Differences Fast
Tired of unreliable VLOOKUP formulas? Compare two Excel columns 3 ways — conditional formatting, COUNTIF/MATCH, or an instant online tool.