The Blog

Check and understand an IP address free online — public vs private, IPv4 vs IPv6, and what your IP does (and doesn't) reveal about you.

Check if a card number is validly formatted with the Luhn algorithm free online — how the checksum works and what it does (and doesn't) prove.

Create clean, SEO-friendly URL slugs free online — why good URLs matter for ranking and clicks, and the rules for writing them.

Convert PDF to JPG images free — no watermark, no signup, and nothing uploaded. Turn every PDF page into a sharp JPG in your browser.

Convert PDF pages to lossless PNG images free — crisp text and lines, no upload, no signup. Done entirely in your browser.

Convert Excel (.xlsx, .xls) to CSV for free in your browser — no software, no signup, and your file is never uploaded. Step-by-step guide.

Copy or extract text from a PDF free online — get clean plain text you can reuse, without uploading your file. Plus what to do with scanned PDFs.

Convert CSV to a real Excel .xlsx workbook for free — columns split correctly, no software, nothing uploaded. Quick browser-based guide.

Learn how to calculate a weighted grade from your scores and their weights — the formula, worked examples, and a free grade calculator.

Convert Excel or CSV to a clean JSON array of objects for free — perfect for APIs, seeding databases and JavaScript. Runs in your browser.

Find out the exact score you need on your final exam to hit your target grade — the formula, examples, and a free final grade calculator.

Convert CSV to JSON and JSON to CSV free in your browser — with correct quoting and nested handling. Simple guide for developers and analysts.