Compare documents and inspect structured data

Practical developer tools and guides

CompareStack is a small set of server-side utilities and the notes that describe their limits. It is for developers, QA, and technical reviewers who already have a snippet, a PDF, a DOCX, or a spreadsheet and need to see a change or make a payload readable.

The tools do not replace Git, an IDE formatter, Track Changes, or a visual PDF proof. They cover the case where the input arrived in a ticket or an email. The writing around them is part of the product: a 30-versus-45-day clause is text extraction, not a pixel diff; a trailing comma is invalid JSON; Base64 is encoding, not encryption.

• Tools — the nine forms, each with its own limits.
• Guides — the longer notes on comparison, formatting, and encoding.
• Examples — one worked input per tool, including when not to use it.
• Documentation — processing, upload limits, and troubleshooting.
• Blog — every article, including ones that are not in the short guide list.

Tarak Moyyi maintains the site independently. The reason for the project is in Why I built CompareStack. Wrong documentation can be reported from the contact page.

Who it is for

CompareStack is for people who already have the text or the file: a developer checking a payload, a reviewer reading two versions of a policy, or someone formatting a query before a ticket. There is no account. The forms run on the server when you submit them. They do not replace Git, Word Track Changes, a visual PDF proof, or a language-aware formatter.

Choose a tool

• Text Compare — line diff of two pastes, up to 100,000 characters a side.
• PDF Compare — wording from the text layer of two PDFs. No OCR and no pixel diff.
• Word Compare — body text from two DOC or DOCX files, not comments or Track Changes.
• Excel Compare — row values from XLS, XLSX, or CSV. Not formulas.
• JSON Formatter — syntax check and indent. Not JSON Schema.
• SQL Formatter — clause line breaks. Not validation or a query plan.
• Code Formatter — brace indentation or HTML layout. Not a language parser.
• URL Encode / Decode and Base64 Encode / Decode — encoding, not encryption.

Start here: best guides

New to CompareStack? These guides explain the workflows behind the tools, then link you back to the matching utility:

• How to Compare Text Efficiently — baseline discipline and clean diffs
• Compare PDF Contracts Online — clause review without missing edits
• Excel Month-End Close Comparison — finance close rhythm
• JSON Validation for API Debugging — validate, format, then diff
• Choosing the Right Document Compare Tool — PDF vs Word vs Excel vs text
• Worked examples — one concrete input per tool, including when not to use it
• Documentation — processing, limits, and troubleshooting

Processing, privacy, and ads

Nothing is compared or formatted until you submit the form. Paste fields accept 100,000 characters. Each upload is limited to 10 MB. Files are read from PHP’s temporary upload for that request and are not copied into a document library. How CompareStack works describes the steps. Privacy covers the session cookie, logs, and Google AdSense. Tarak Moyyi maintains the site; the About page is the accurate description, and support@comparestack.in is the contact address.