Our free online LCS calculator helps you find the longest sequence of characters that appear in the same order in both strings. Whether you’re a student, programmer, or researcher, this tool simplifies string comparison, DNA sequence analysis, and text diffing with just a few clicks.
Longest Common Subsequence Calculator
Results:
What is the Longest Common Subsequence (LCS)?
The Longest Common Subsequence (LCS) is a fundamental algorithm in computer science and bioinformatics that identifies the longest sequence of characters shared between two strings in the same order (but not necessarily consecutively).
How to Use Our LCS Calculator
Our interactive LCS calculator makes it easy to find the longest matching subsequence:
- Enter your first sequence (e.g., “ABCBDAB”).
- Enter your second sequence (e.g., “BDCAB”).
- Click “Calculate LCS”.
- View Results:
- LCS String (e.g., “BCAB”).
- LCS Length (e.g., 4).
- Visual DP Matrix (showing how LCS is computed).
Example: LCS of “ABCBDAB” and “BDCAB”
| Sequence 1 | A | B | C | B | D | A | B |
| Sequence 2 | B | D | C | A | B | | |
LCS Result: “BCAB” (Length: 4)
Why Use Our LCS Calculator?
- Fast & Accurate – Uses dynamic programming for optimal results.
- Step-by-Step Visualization – See the DP matrix for better understanding.
- No Installation Needed – Works directly in your browser.
- Free & No Limits – Calculate LCS as many times as you need.
Frequently Asked Questions
1. What’s the difference between LCS and Longest Common Substring?
- LCS finds characters in order (not necessarily consecutive).
- Longest Common Substring requires characters to be contiguous.
2. What is the time complexity of LCS?
The standard LCS algorithm runs in O(mn) time, where m and n are the lengths of the two sequences.
3. Can LCS be used for DNA sequence matching?
Yes! LCS is widely used in bioinformatics for comparing DNA, RNA, and protein sequences.
4. How is LCS used in Git and version control?
Git uses LCS-based diff algorithms to highlight changes between file versions.
References: https://en.wikipedia.org/wiki/Longest_common_subsequence
Also see:
Image Converters | Unit Converters
