Guides, Tips and How-Tos
Practical step-by-step guides for common PDF, image, data and date tasks — written to help you get better results with free online tools.
How to Compress a PDF Online (Without Losing Quality)
Learn how to reduce PDF file size for email and uploads, which settings to use, and why some PDFs shrink more than others.
Read guide →GuideHow to Convert PNG to JPG (and When You Should)
Understand the difference between PNG and JPG, when converting saves space, how transparency is handled and how to convert images free online.
Read guide →GuideHow to Merge PDF Files Into One Document
Combine multiple PDF files into a single PDF in the right order. Step-by-step guide plus tips for scans, page order and file size.
Read guide →GuideHow to Resize an Image for a Website (Size Guide)
Recommended image sizes for websites, blogs and social media, plus how to resize, compress and choose the right format for fast pages.
Read guide →GuideHow to Format and Validate JSON (With Common Errors)
Learn how to pretty-print and validate JSON, understand the most common JSON syntax errors and fix them quickly with a free online formatter.
Read guide →GuideHow to Calculate Age From a Date of Birth
Calculate exact age in years, months and days from a date of birth. Learn the method, leap-year rules and how to use a free age calculator.
Read guide →