Duplicate Line Remover

Remove duplicate lines from any text instantly. Keep only unique entries while preserving the original order — perfect for cleaning lists, database exports, email addresses, and log files. Free, private, no login.

100% PrivateInstantAny DeviceNo Sign-Up

Options

How to Remove Duplicate Lines from Text

Follow these simple steps to deduplicate your text. It takes just seconds — no technical knowledge required.

1

Paste or Upload Your Text

Enter your text in the input box above, with one item per line. You can also click "Upload .txt file" to load text from a file on your device.

2

Choose Your Options

Select whether the comparison should be case-sensitive, whether to trim whitespace from each line, and whether to remove empty or blank lines from the result.

3

Click "Remove Duplicates"

Press the button to process your text. Duplicate lines are removed instantly, keeping only unique entries in their original order.

4

Copy or Download the Result

Your deduplicated text appears in the Output box. Click "Copy" to copy it to your clipboard or "Download" to save it as a .txt file.

Why Use Our Free Duplicate Line Remover?

A fast, private, and reliable deduplication tool built by professional developers at CoderDesign Toronto. Here is what makes it different.

Instant Deduplication

Remove thousands of duplicate lines in milliseconds. No waiting, no server uploads — everything runs instantly in your browser with zero latency.

100% Private & Secure

Your text never leaves your device. All processing happens locally in your browser. No data is stored, sent to servers, or tracked in any way.

Works on Any Device

Use this tool on desktop, tablet, or mobile. Compatible with Chrome, Firefox, Safari, Edge, and all modern browsers — no installation needed.

File Upload Support

Upload .txt files directly and process them instantly. Download your deduplicated output as a clean file when you are done.

Smart Comparison

Choose case-sensitive or case-insensitive matching, trim leading and trailing whitespace, and optionally strip empty lines for maximum flexibility.

No Sign-Up Required

Start using the tool immediately. No login, no account creation, no email required. Free forever — just paste your text and get results.

Common Use Cases

See how developers, marketers, and data analysts use the duplicate line remover to save hours of manual editing.

Clean Database Exports

Remove repeated rows from database dumps or CSV exports.

Before

John Doe, Toronto
Jane Smith, Vancouver
John Doe, Toronto
Mark Lee, Calgary

After

John Doe, Toronto
Jane Smith, Vancouver
Mark Lee, Calgary

Deduplicate Email Lists

Clean up email lists before sending campaigns.

Before

alice@example.com
bob@example.com
alice@example.com
charlie@example.com

After

alice@example.com
bob@example.com
charlie@example.com

Remove Duplicate Imports

Clean up source code files by removing repeated import statements that accumulate during development and copy-pasting.

Before

import React from 'react';
import axios from 'axios';
import React from 'react';
import lodash from 'lodash';

After

import React from 'react';
import axios from 'axios';
import lodash from 'lodash';

Clean Survey Responses

Consolidate survey or form responses by removing repeated answers to get a clean list of unique entries.

Before

Very Satisfied
Satisfied
Very Satisfied
Neutral

After

Very Satisfied
Satisfied
Neutral

Deduplicate Log Files

Strip repeated log entries from server or application logs to focus on unique events and simplify debugging.

Before

[INFO] Server started on port 3000
[WARN] Disk usage 85%
[INFO] Server started on port 3000
[ERROR] Connection timeout

After

[INFO] Server started on port 3000
[WARN] Disk usage 85%
[ERROR] Connection timeout

Frequently Asked Questions

Everything you need to know about removing duplicate lines from text. Can't find what you're looking for? Contact us.

The duplicate line remover scans your text line by line and keeps only the first occurrence of each unique line. All subsequent duplicates are removed, leaving you with a clean list of unique entries. The original order of first appearances is always preserved, so your data stays organized exactly the way you intended.
Simply paste your text into the input box with each item on a separate line. Choose your preferred options — case sensitivity, whitespace trimming, and empty line removal — then click "Remove Duplicates". The deduplicated text appears instantly in the output box, ready to copy or download as a .txt file.
Yes, absolutely. The tool preserves the order of first appearances. When a duplicate line is encountered, only the first occurrence is kept in its original position while all later duplicates are removed. This means your data stays in the same sequence — only the repeats are stripped out.
By default, yes — "Apple" and "apple" are treated as different lines. However, you can toggle case sensitivity off by unchecking the "Case sensitive" option. When case-insensitive mode is enabled, lines that differ only in letter casing are treated as duplicates and only the first occurrence is kept.
Yes, this duplicate line remover is completely free with no limitations whatsoever. There are no hidden charges, no premium tiers, and no sign-up required. You can process unlimited lines of text as many times as you need. CoderDesign provides this tool as a free resource for the developer and data community.
Absolutely. All text processing happens entirely in your browser using JavaScript — nothing is sent to any server. Your text is never stored in any database, logged, or shared with any third party. You can verify this yourself by using the tool with your browser in offline mode after the page has loaded.
Yes. Simply enable the "Remove empty lines" checkbox and the tool will strip all blank lines from the output in addition to removing duplicates. This is especially useful for cleaning up text files that have extra line breaks, or when you want a compact list with no gaps between entries.
There is no hard limit on the number of lines you can process. Because everything runs locally in your browser, performance depends on your device. Documents with 10,000+ lines typically process in well under a second on modern devices. For extremely large files (100,000+ lines), performance remains excellent on desktop browsers.

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