100% Private
Your config files and API data never leave your device. Safely inspect sensitive configs and secrets.
Free Online Developer Tools
View JSON, XML, YAML, TOML, HAR, and Avro files with syntax highlighting, collapsible tree views, and schema inspection. No extensions needed — 100% in your browser.
🔒 100% Private
🔧 6 Developer Formats
🌲 Tree View
Developer & Config Viewers
View structured data, config files, and network traces
JSON Viewer
Explore JSON data with syntax highlighting, collapsible tree view, and search. Navigate deeply nested structures with ease.
Open JSON Viewer →XML Viewer
Explore XML files with collapsible tree view, attribute display, and syntax highlighting.
Open XML Viewer →YAML Viewer
View YAML configuration files (Kubernetes, Docker Compose, CI/CD pipelines) with structured tree view.
Open YAML Viewer →TOML Viewer
View TOML config files (Cargo.toml, pyproject.toml, Hugo) with structured tree view and section navigation.
Open TOML Viewer →HAR Viewer
Analyze HTTP Archive files with request list, status code breakdown, timing data, and response details.
Open HAR Viewer →Avro Viewer
View Apache Avro data files with schema inspection, record browser, and data preview.
Open Avro Viewer →Inspect Developer Files Without Extensions
DataViewer parses structured data and config files directly in the browser with clean, interactive tree views. No browser extensions, no CLI tools — just drag and drop.
Our developer tools are ideal for:
- API debugging — Inspect JSON responses and HAR network traces
- Config review — View YAML (Kubernetes, Docker), TOML (Cargo, pyproject), and XML configs
- Data engineering — Inspect Apache Avro schemas and records
- Performance analysis — Analyze HAR files exported from browser DevTools
- Code review — Preview structured data files without cloning a repo
Features Across All Developer Tools
- Collapsible Tree ViewExpand and collapse nodes to navigate complex structures
- Syntax HighlightingColor-coded keys, values, strings, numbers, and booleans
- Schema InspectionView Avro schemas, XML attributes, and YAML anchors
- HAR AnalysisRequest timeline, status codes, response sizes, and timing
- Search & NavigateFind keys and values in large JSON and XML files
- 100% Client-SideAll processing happens locally — files never leave your device
Why Use DataViewer for Dev Files?
The fastest way to inspect structured data online
Interactive Trees
Collapsible tree views make it easy to navigate even deeply nested JSON, XML, and YAML structures.
Syntax Highlighting
Color-coded display makes it easy to distinguish keys, values, strings, numbers, and nested objects.
Zero Setup
No extensions, no CLI tools, no npm packages. Just open the page and drop your file.
Developer Tools FAQ
What developer file formats are supported?
We support JSON (with collapsible tree view and search), XML (with attribute display), YAML (Kubernetes, Docker, CI/CD configs), TOML (Cargo.toml, pyproject.toml), HAR (HTTP Archive from browser DevTools), and Apache Avro (schema and data files).
Can I safely view config files with secrets?
Yes. All file processing happens 100% in your browser. Your config files — including those with API keys, passwords, or tokens — are never uploaded to any server. They stay on your device at all times.
How do I analyze a HAR file?
Export a HAR file from your browser's DevTools (Network tab → Export HAR), then drop it into our HAR viewer. You'll see a request list with status codes, response sizes, timing data, and the ability to inspect individual request/response details.
Can I view large JSON files?
Yes! The JSON viewer supports files up to 20MB with a collapsible tree view that handles deeply nested structures efficiently. Expand only the nodes you need to inspect.
What's the difference between the JSON and YAML viewers?
Both provide structured tree views, but each is optimized for its format. The JSON viewer handles JSON-specific features (arrays, nested objects, null values), while the YAML viewer handles YAML-specific features (anchors, references, multi-line strings, comments).
What is an Avro file?
Apache Avro is a data serialization format used in big data and event streaming systems (Kafka, Hadoop). Our Avro viewer lets you inspect the schema definition and browse individual records without setting up a Java environment.