Diff Viewer
Compare code, configs, or API responses. Securely in your browser — no uploads, no tracking.
function greet(name) { console.log("Hello, " + name); return "Welcome!";}
function greet(name, title = "Guest") { console.log(`Hello, ${title} ${name}!`); return `Welcome, ${title} ${name}!`;}
Comparison happens locally. Your text never leaves your device.
Why use a local diff tool?
Comparing configuration files, API responses, or large JSON schemas often involves sensitive production data. Online diff tools require you to paste your content into their servers to process it.
SyntaxSnap calculates differences directly in your browser using client-side JavaScript — your data stays in your device's RAM and is never transmitted.
Perfect for reviewing merge conflicts, checking environment variable changes, or auditing config drift between staging and production.
Common Use Cases
- • Code review: Compare versions before/after a refactor
- • API debugging: Spot payload changes between requests
- • Config audits: Check .env or nginx.conf drift
- • Merge conflicts: Understand what changed in git diffs
Frequently Asked Questions
Is my data sent to a server?
No. SyntaxSnap calculates the diff entirely in your browser using the JavaScript diff library. Your text never leaves your device and is not uploaded anywhere.
What file types can I compare?
Any plain text format: code (JS, Python, Java, etc.), JSON, YAML, XML, CSV, config files (.env, nginx.conf), logs, API responses, and more. Just paste the content into the text boxes.
What is the difference between line-level and word-level diff?
Line-level highlights entire lines that changed. Word-level shows exactly which words within a line were modified — useful for spotting small typos or single-word changes.
Can I compare large files?
Yes. The tool uses debounced diff calculation to handle large files smoothly. For extremely large files (10MB+), performance depends on your browser and device specs.
Is my code secure when using the SyntaxSnap Diff Viewer?
Yes. Unlike other online diff tools, SyntaxSnap calculates text differences entirely client-side. Your code, API keys, or sensitive logs never leave your browser and are never transmitted to a server.
What is the difference between line-level and word-level diffing?
Line-level diffing identifies changed blocks of code, while word-level diffing highlights exact character changes within a line. This is ideal for spotting subtle typos or logic changes in dense files like JSON or YAML.
Can I compare large log files or JSON payloads?
Yes. Our tool uses debounced, non-blocking algorithms to compare large text files efficiently. It handles configuration files, ENV variables, and production logs smoothly without freezing your browser tab.
Explore More Developer Tools
Boost your productivity with our other privacy-first utilities.
AI Mock Generator
Generate realistic mock data from natural language prompts. Runs entirely in your browser — no API keys required, no data leaves your machine.
JWT Debugger
Decode, inspect, and validate JWT token headers and payloads without sending credentials to any server. Fully offline, privacy-first debugging.
Aurora Gradient Generator
Create animated, pure CSS aurora backgrounds and mesh gradients. Generate Tailwind classes or raw CSS instantly. 100% local, privacy-first execution.