A collection of online utilities to help you work efficiently.
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Base64 shows up everywhere — email attachments, JWT tokens, embedded images. This guide explains what Base64 encoding is, how it works, common uses, and how to encode or decode any string online.
Buying a home and need to know your monthly payment? This guide explains the mortgage payment formula, how interest rate and loan term affect your costs, and how to use an online mortgage calculator.
Need to save PDF pages as images? This guide shows how to convert PDF to JPG online in seconds — batch convert all pages, choose your resolution, and download instantly for free.
Need a QR code for a URL, WiFi password, or contact card? This guide explains QR code types, error correction levels, and how to generate a high-quality QR code in seconds — free, no sign-up.
Compound interest is the engine behind long-term wealth growth. Learn the formula, see real examples, compare frequencies, and calculate your investment's future value instantly.
Ever seen %20 or %2F in a URL and wondered what they mean? This guide explains URL encoding, shows common character codes, and shows you how to encode or decode any URL string instantly.
BMI (Body Mass Index) is one of the most common tools for assessing healthy weight. Learn the BMI formula, healthy BMI ranges for Asian populations, its limitations, and how to calculate yours instantly online.
Need to extract specific pages from a large PDF? This guide walks you through splitting PDFs online in seconds — pick any page range, free, no software needed.
Need to turn photos or scanned images into a PDF? This guide shows you how to convert JPG, PNG, and other images to PDF in seconds — free, no installation, works on any device.
Need to combine multiple PDF files into one? This guide walks you through merging PDFs online in seconds — no software installation, no account required, completely free.
JSON has become the lingua franca of modern web development. This article explores how a powerful formatting tool can boost your debugging efficiency, catch syntax errors, and help you visualize complex data structures.
Learn the easiest and most secure ways to convert your JPG and PNG images into high-quality PDF documents. Discover why PDF is the preferred format for sharing and how to maintain image resolution during conversion.
Struggling with the notorious 'JSONDecodeError: Expecting value: line 1 column 1 (char 0)'? Learn how to trace invalid quotes, empty API responses, and trailing commas to save hours of debugging.
JWT Debugger is an online tool for parsing, verifying, and debugging JSON Web Tokens. It supports HS256, RS256, and other algorithms.
totp-generator is a simple, lightweight, and reliable local TOTP generator built on RFC 6238.
Sometimes a photo looks fine on your phone or computer, but rotates after being uploaded. This happens due to the Exif orientation metadata.
Exif (Exchangeable Image File Format) is a metadata standard embedded in image files, storing details such as device, time, aperture, shutter speed,...