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Talk on the boards and keep your links, notes, places and reviews in one place.

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Ready-to-use tools

No login, right in your browser — calculator, dates, images, PDF, QR and passwords

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Calculator

A calculator from basic arithmetic to trigonometry and logs, plus VAT, discount, percent, bill-splitting, loan-interest and amount-in-words calculators, and unit/date expressions such as “5km + 300m to mi” or “today + 100 days”. Everything is computed on this page and history stays in this browser.
Age & Date Calculator

Korean legal age, D-day, 100-day and yearly anniversaries, the span between two dates, N days or months later, and business days excluding holidays.
Image Tools

Shrink, crop and adjust photos, paint with a brush, stack images as layers, and remove location data (EXIF). Also makes favicon sets, picks key colors and converts to Base64. Files never leave your browser.
PDF Tools

Merge PDFs, delete, rotate and reorder pages, save PDF pages as images, or bundle images into a PDF. Files are processed only in this browser and never uploaded.
QR Code Generator

Turn a link, text, Wi‑Fi login or contact (vCard) into a QR code and download it as PNG or SVG. No login needed, and what you type is not stored.
Password Generator

Create a hard-to-guess password from a length and character types, or as an easy-to-remember word combination (passphrase). The result never leaves this page.
Unit converter

Convert length, weight, temperature, area and volume, including traditional Korean units such as pyeong, geun, don and ja.
Developer Tools

Twenty-eight everyday developer helpers in one place (now with subnet/CIDR, chmod, an HTTP/MIME/port reference, robots/sitemap and dummy data): URL, Base64, HTML and Unicode encoding, JSON formatting, CSV and type generation, Unix time, JWT decoder, hashes, UUIDs, regex, text diff, number bases, cron, certificate/CSR and mail header readers, business registration number checks, and a table converter.