File Format Guides
Comprehensive guides for popular file formats. Learn the structure, history, use cases, advantages, and technical details of each format.
Documents
application/pdf
PDF (Portable Document Format) is a universal file format for sharing documents with preserved formatting across all platforms and devices.
DOCX
application/vnd.openxmlformats-officedocument.wordprocessingml.document
DOCX is the default document format for Microsoft Word, based on the Office Open XML (OOXML) standard for rich text documents.
Code & Data
JSON
application/json
JSON (JavaScript Object Notation) is a lightweight, human-readable data interchange format used universally in web APIs, configuration files, and data storage.
XML
application/xml
XML (Extensible Markup Language) is a flexible, self-describing markup language for structured data used in web services, configuration, and document formats.
HTML
text/html
HTML (HyperText Markup Language) is the standard markup language for creating web pages and web applications.
YAML
text/yaml
YAML (YAML Ain't Markup Language) is a human-readable data serialization format widely used for configuration files and data exchange.
Spreadsheets
CSV
text/csv
CSV (Comma-Separated Values) is a plain-text tabular data format universally supported by spreadsheets, databases, and programming languages.
XLSX
application/vnd.openxmlformats-officedocument.spreadsheetml.sheet
XLSX is the default spreadsheet format for Microsoft Excel, based on the Office Open XML standard for tabular data and calculations.
Images
PNG
image/png
PNG (Portable Network Graphics) is a lossless image format supporting transparency, widely used for web graphics, screenshots, and digital artwork.
JPG
image/jpeg
JPEG (JPG) is the most widely used lossy image format, ideal for photographs and complex images with millions of colors.
SVG
image/svg+xml
SVG (Scalable Vector Graphics) is an XML-based vector image format for two-dimensional graphics that scales to any size without quality loss.
GIF
image/gif
GIF (Graphics Interchange Format) is a bitmap image format supporting animation and transparency, widely used for short looping animations.
WebP
image/webp
WebP is a modern image format developed by Google that provides superior lossy and lossless compression for web images.
Understanding File Formats
File formats define how data is encoded, structured, and stored in files. Understanding file formats is essential for developers, testers, data analysts, and anyone working with digital files. Our guides cover the most commonly used formats across documents, code, data, images, and video.
For Developers
Learn about MIME types, magic bytes, file structure, and encoding details. Understand how to parse, validate, and generate files in different formats. Use our online tools to validate and inspect files.
For Testing Teams
Understand format specifications to create better test cases. Download sample files for every format, or generate custom test files with specific properties.