Tool Overview

The Changelog Generator turns your Git commit messages into organized changelog documents. You paste a list of commit messages, and the tool automatically groups them by type, formats them according to your preferences, and creates a changelog ready to share with your team or users. It follows the Keep a Changelog format and supports both Markdown and plain text output.

Creating changelogs manually is time-consuming and inconsistent. You need to read through many commits, categorize them, write clear descriptions, and format everything properly. Different team members might organize changes differently, making changelogs hard to read. This generator handles the categorization and formatting automatically, so you can focus on reviewing the content instead of organizing it.

The tool is designed for developers, project maintainers, and release managers. Beginners can learn changelog structure by seeing how commits become organized documents. Experienced users can quickly generate changelogs without manual formatting. Teams benefit from consistent changelogs that make releases easier to communicate.

Background & Concept Explanation

A changelog is a document that lists changes made to a project over time, usually organized by version or date. Good changelogs group changes by type such as new features, bug fixes, improvements, and breaking changes. They help users understand what is new, what is fixed, and what might require action when upgrading.

Many teams struggle with changelogs because they are written after work is done, when details might be forgotten. They might miss important changes, group things inconsistently, or write descriptions that are too technical or too vague. Without a standard format, changelogs become hard to read and less useful.

The Changelog Generator addresses this by reading your actual commit messages and applying consistent rules. It recognizes conventional commit patterns like feat, fix, perf, and breaking change indicators. It groups similar changes together and formats them according to your chosen style. This means the changelog reflects what actually happened in your commits, organized in a clear, consistent way.

Key Features

• Raw commit message input. You paste commit messages into a large text area, one per line or separated by newlines. The tool accepts up to 10,000 characters of input, which covers most typical release cycles. You can paste directly from Git log output or type messages manually.
• Automatic commit categorization. The parser examines each commit message and assigns it to a category. It looks for keywords like feat or feature to identify new features, fix or bug to identify bug fixes, perf or optimize to identify improvements, and break or exclamation marks to identify breaking changes. Messages that do not match specific patterns go into an other category.
• Breaking change detection. The parser prioritizes breaking changes by checking for the word break, exclamation marks, or prefixes like breaking: or !breaking. These are always placed in a Breaking Changes section at the top of the changelog, regardless of other keywords in the message.
• Line length protection. The parser limits individual commit lines to 500 characters to prevent extremely long messages from causing display issues. Lines longer than this limit are truncated with an ellipsis, keeping the changelog readable.
• Prefix cleaning. The tool removes common prefixes like bullet points, numbers, dashes, and parentheses from the start of commit messages. This handles cases where commits are copied from formatted lists or include numbering, ensuring clean output.
• Target audience selection. You can choose between Developer and User audiences. This setting affects how the changelog is formatted and worded, though the core structure remains the same. Developer changelogs might use more technical language, while User changelogs focus on benefits.
• Output format options. You can choose between Markdown format, which uses headers and bullet points suitable for documentation sites, or Plain Text format, which uses simple text formatting suitable for emails or plain text files. Both formats follow the same structure but use different markup.
• Emoji inclusion toggle. A switch lets you enable or disable emojis in section headers. When enabled, sections show emojis like warning for breaking changes, rocket for new features, bug for bug fixes, lightning for improvements, and memo for other changes. When disabled, headers are text-only.
• Real-time preview. As soon as you generate a changelog, it appears in a preview panel on the right side. The preview updates automatically when you change audience, format, or emoji settings, so you can see how different options affect the output.
• Sample input buttons. When the input area is empty, the tool shows three sample input sets. Each sample contains realistic commit messages demonstrating different types of changes. Clicking a sample loads it into the input area and automatically generates a changelog, helping you understand how the tool works.
• Local storage persistence. The tool automatically saves your input to browser storage. When you return to the page, it restores your previous commit messages so you can continue working or refine the changelog. This makes it easy to iterate on changelogs over multiple sessions.
• Copy to clipboard functionality. A copy button appears in the preview header when content is generated. Clicking it copies the entire changelog to your clipboard, and a notification confirms the copy succeeded. This makes it easy to paste the changelog into documentation, release notes, or other documents.
• AI-powered enhancement. An optional Enhance with AI button sends your generated changelog to a backend AI service. The AI refines the language, improves clarity, and adapts the tone for your chosen audience. The enhanced version replaces the original in the preview, and you can copy it or revert if needed.
• Character count display. The tool shows how many characters you have entered out of the maximum allowed. When you approach 90 percent of the limit, it shows a warning message. This helps you stay within bounds and understand when your input might be getting too large.
• Input validation and error handling. The tool checks that input is not empty, does not exceed length limits, and contains valid content. If validation fails, it shows clear error messages explaining what went wrong and how to fix it.

Common Use Cases

A release manager prepares release notes for version 2.0. They run git log to get all commits since the last release, copy the commit messages, and paste them into the generator. The tool categorizes features, fixes, and breaking changes, and generates a Markdown changelog. They review it, enable AI enhancement for a User audience, and copy the polished result into their release documentation.

A developer wants to document changes in a pull request. They list the commit messages from the PR, paste them into the generator, and select Developer audience with Markdown format. The tool creates a changelog showing what the PR adds, fixes, and improves. They copy it and add it to the PR description.

A team lead needs to communicate updates to stakeholders. They gather commit messages from the last sprint, paste them into the generator, choose User audience and Plain Text format, and enable emojis. The tool creates a user-friendly changelog that highlights new features and fixes. They use AI enhancement to make the language more accessible, then copy it into an email.

An open source maintainer updates their project changelog file. They collect commits from the latest release, paste them into the generator, and generate a Markdown changelog with emojis. They review the categorization, make minor edits, and copy the result into their CHANGELOG.md file.

How to Use This Tool (Step-by-Step)

1. Open the Changelog Generator. You will see an input area on the left and a preview panel on the right.
2. If you want to see how it works, click one of the sample input buttons when the input area is empty. This loads example commit messages and automatically generates a changelog.
3. To use your own commits, gather commit messages from your Git history. You can run git log --oneline to get a simple list, or git log --pretty=format:"%s" to get just the subject lines. Copy the messages you want to include.
4. Paste the commit messages into the input text area on the left. You can paste one message per line or multiple messages separated by newlines. The tool will process them all.
5. Check the character count below the input area. Make sure you stay within the 10,000 character limit. If you see a warning about approaching the limit, consider splitting your changelog into multiple versions.
6. Click the Generate Changelog button. The tool will parse your commits, categorize them, and create a formatted changelog. The result appears in the preview panel on the right.
7. Review the generated changelog. Check that commits are categorized correctly, breaking changes appear first, and the overall structure makes sense. The changelog follows Keep a Changelog format with sections for Breaking Changes, New Features, Bug Fixes, Improvements, and Other Changes.
8. Adjust your preferences if needed. Use the Target Audience toggle to switch between Developer and User. Use the Output Format toggle to choose Markdown or Plain Text. Toggle Include Emojis on or off. The preview updates automatically as you change these settings.
9. If you want more polished language, click the Enhance with AI button below the preview. Wait for the AI to process your changelog. When it finishes, the preview updates with an enhanced version that has improved clarity and tone for your chosen audience.
10. When you are satisfied with the changelog, click the copy button in the preview header. A notification will confirm that the changelog was copied to your clipboard.
11. Paste the changelog into your documentation, release notes, or wherever you need it. You can edit it further in your editor if needed, but the generator provides a solid foundation.
12. If you want to start over, clear the input area and paste new commit messages. The tool will generate a fresh changelog based on the new input.

Calculations & Logic

The Changelog Generator processes commit messages through parsing and formatting steps. First, it validates that the input is a non-empty string. If the input is empty or invalid, it returns an empty ParseResult with no items in any category.

Next, it splits the input by newlines and processes each line. It trims whitespace from each line and filters out completely empty lines. It also limits each line to 500 characters, truncating longer lines and adding an ellipsis to prevent display issues.

For each non-empty line, the parser removes common prefixes like bullet points, numbers, dashes, and parentheses. This cleaning step ensures that formatted lists or numbered commits produce clean output without extra characters.

The parser then categorizes each cleaned line by examining its content. It converts the line to lowercase for case-insensitive matching. It checks for breaking change indicators first, including the word break, exclamation marks, or prefixes like breaking: or !breaking. If found, the line goes into the breaking array.

If not a breaking change, the parser checks for feature indicators. It looks for lines starting with feat or feature, or containing keywords like added, add, new, or implement. Matching lines go into the features array.

If not a feature, it checks for bug fix indicators. It looks for lines starting with fix or bugfix, or containing keywords like bug, patch:, resolve, or correct. Matching lines go into the fixes array.

If not a fix, it checks for improvement indicators. It looks for lines starting with perf, refactor, improve, optimize, style:, or chore:, or containing the word enhance. Matching lines go into the improvements array.

Any line that does not match the above patterns goes into the other array. This ensures that all commits are included in the changelog, even if they do not follow conventional commit format.

To generate the changelog, the formatter creates section objects for Breaking Changes, New Features, Bug Fixes, Improvements, and Other Changes. Each section includes a title, the array of items from parsing, and an emoji. Sections with no items are filtered out, so empty categories do not appear.

For Markdown format, the generator creates a header, then iterates through sections. For each section, it writes a level 2 header with optional emoji, then lists items as bullet points. For Plain Text format, it uses uppercase headers with underlines, then lists items with bullet characters.

The final output is trimmed to remove trailing whitespace and returned as a single string. This string appears in the preview panel and can be copied or enhanced with AI.

For AI enhancement, the tool sends the generated changelog and audience type to a backend service. The service validates input length and audience, then returns an enhanced version. If the service fails or returns invalid data, the tool falls back to the original changelog, ensuring you never lose your work.

Tips, Limitations & Best Practices

Use conventional commit format in your commit messages for best results. Messages that start with feat, fix, perf, or include breaking change indicators are categorized more accurately. If your team does not use conventional commits, you can still use the tool, but you might need to review categorization more carefully.

Keep commit messages clear and descriptive. Vague messages like updated code or fixed stuff produce vague changelog entries. More specific messages like fix: resolve memory leak in image processing create better changelog content.

Review the generated changelog before using it. The parser uses pattern matching, so it might occasionally miscategorize commits. Check that breaking changes are highlighted, features are grouped correctly, and important changes are not lost in the other category.

Use AI enhancement when you want more polished language, especially for User audiences. The AI can make technical descriptions more accessible and improve overall clarity. However, always verify that enhanced content accurately reflects your changes.

Consider splitting very large changelogs. If you have hundreds of commits, the generated changelog might be too long to be useful. Consider generating changelogs for specific time periods or versions instead of one massive document.

Use the appropriate audience setting. Developer changelogs can be more technical, while User changelogs should focus on benefits and avoid jargon. The AI enhancement adapts to your audience choice, so make sure it matches your intended readers.

Finally, remember that changelogs are communication tools. Even with automatic generation, take time to ensure the final document clearly communicates what changed and why it matters. A well-written changelog helps users understand updates and makes your project more professional.