Guides
Short, practical guides for getting the most out of Tool King.
How to convert PDF to Word in seconds
Turn a PDF into an editable .docx file without installing any software — free, fast, and it works right in your browser.
Read guideHow to merge multiple PDF files into one
Combine invoices, reports or scanned pages into a single PDF, in the order you choose — free, with no file size limit to worry about.
Read guideHow to make a PDF smaller for email or upload
Shrink a PDF that's too large to email or upload, without losing content — free, and nothing stays on our server afterward.
Read guideThe best way to compress images without losing quality
Reduce JPG, PNG or WebP file size while keeping images sharp enough for the web — free, with a quality slider you control.
Read guideHow to resize an image to exact dimensions
Set the exact width and height you need — for a website, a form, or social media — free, with an aspect-ratio lock to avoid distortion.
Read guideA quick guide to formatting and validating JSON
Turn minified or messy JSON into something readable — and catch syntax errors fast, right in your browser, free and private.
Read guideHow to convert Markdown to Word (DOCX)
Turn a README, spec or notes file into a properly formatted Word document — free, preserving headings, lists and tables.
Read guideHow to convert PDF to Markdown
Pull a PDF's content back into plain-text Markdown for editing, diffing or publishing — free, with headings detected automatically.
Read guideWhat is DNS? A plain-English explanation
How your browser turns a domain name like example.com into the server it actually talks to — explained in plain English.
Read guideWhat is SSL? Understanding the padlock in your browser
Why that little padlock icon matters, and what it actually verifies — explained in plain English, with no security jargon required.
Read guideHow HTTPS actually works, step by step
The handshake that happens before a single byte of a webpage is loaded — explained step by step, in plain, jargon-free English.
Read guideWhat is a VPN, and what does it actually hide?
What a VPN protects you from — and the common leak that quietly undermines it, explained without any of the marketing jargon.
Read guideHow to secure your home Wi-Fi network
The handful of router settings that actually matter for keeping your home network safe — no networking background required at all.
Read guideHow to check your IP address (and what it reveals)
The difference between your public and private IP, and what a lookup actually shows you — explained simply, with no jargon.
Read guideHow to protect your website: a practical checklist
The concrete, non-negotiable basics before you worry about anything more advanced — a practical, no-nonsense security checklist.
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