Free Text Compare Tool — Find Differences Between Two Texts Instantly
Our free text compare tool highlights every difference between two pieces of text in real time. Unlike most diff checkers that only show which lines changed, our tool also highlights the exact words that changed within each modified line. Choose between side-by-side split view or unified inline view, toggle case and whitespace sensitivity, and see a similarity percentage score alongside full statistics on added, removed, and modified lines. Works with plain text, code, articles, legal documents, and any other text-based content.
How to Compare Two Texts Online — Step by Step
Paste your original text into the left panel. Paste your modified text into the right panel. The diff output appears immediately — no button to click. Lines in red show content removed from the original. Lines in green show content added in the modified version. Lines in amber show lines that changed, with specific changed words marked in darker highlighting within each line. Use split view for longer documents or unified view for a compact Git-style single-column output.
Text Compare for Developers — Code Review and Git Diffs
Developers use text comparison tools daily for code reviews, pull request previews, debugging configuration changes, and tracking API response differences. Our tool works with any programming language — JavaScript, TypeScript, Python, Java, Go, Rust, HTML, CSS, SQL, JSON, XML, and YAML. Line numbers are displayed alongside every line for precise reference. The Ignore Whitespace toggle is particularly useful for comparing code that was reformatted without changing its logic. For JSON comparison, paste minified and formatted versions to instantly see structural differences, then use our free JSON Formatter to clean up the result.
Text Compare for Writers, Editors, and Content Teams
Writers and editors use text comparison to track revisions between document drafts, review editorial changes before publishing, verify sections were not modified during translation, and compare submitted content against published versions. The word-level diff highlighting makes proofreading significantly faster — instead of reading both versions word by word, your eye is immediately drawn to the changed words highlighted in each modified line. The similarity score helps content managers assess how substantially a draft was revised compared to the previous version.
Text Compare for SEO — Tracking Content Changes
SEO professionals use text comparison to track changes made to competitor pages over time, verify that on-page optimizations were correctly implemented, compare a page before and after a Google algorithm update, and audit content updated by a team member before republishing. Paste the before and after versions of any page to immediately see every word added or removed. This workflow is especially valuable when analyzing pages that gained or lost rankings — the diff shows exactly what content changed. Combine this with our Word Counter to check whether content length changes contributed to ranking shifts.
Split View vs Unified View — When to Use Each
Split view shows the original and modified texts in two columns side by side — best for comparing longer documents or prose where you need to read both versions in full context. It mirrors the two-panel format used in Microsoft Word's Compare Documents and VS Code's diff viewer. Unified view (inline diff) shows all changes in a single column with removed lines in red and added lines in green — this is the format produced by Git diff commands and is best for quickly scanning many small changes in code or configuration files.
Understanding the Diff Algorithm
Our text compare tool uses the Longest Common Subsequence algorithm to find the minimum number of insertions and deletions needed to transform the original text into the modified version. This finds the optimal diff — preserving as much unchanged content as possible. For changed lines, a second pass runs at the word level to identify exactly which words changed. This two-pass approach gives you both line-level context and word-level precision in a single view.