Learn how to solve classic puzzles, optimize client-side workflows, and protect your privacy with local-first browser tools.
Can't solve your 15-puzzle or 8-puzzle? Learn the 4-step method and corner techniques for solvable sliding tile puzzles. Includes illustrations, parity checks, and our free solver.
Learn how to estimate your hourly rate using scheduled hours from a Japanese monthly or annual salary. Understand the different purpose-specific wage bases for overtime calculations and minimum wage checks under Japanese labor laws.
Learn how to calculate a weighted split based on agreed ratios and effectively manage rounding differences for groups with varying needs, such as latecomers or non-drinkers, to handle surplus or deficit smoothly.
A digital bookshelf utilizing the browser's IndexedDB to save manga volumes individually. Explains the search function to prevent duplicate purchases, external API registration assistance, and device-specific data storage limits.
Email header (raw source) is a record of the servers that an email went through before arriving. In this article, we explain the role of an email header analysis tool, identifying delivery routes with the Received header, understanding SPF/DKIM/DMARC authentication, and procedures for parsing headers in your browser without automatic external verification.
A detailed guide on the specifications, product assumptions, and limitations of the 2026 limited annual tax simulator for residents of Japan.
Learn about OCR (Optical Character Recognition) for extracting text from images. We explain how in-browser processing works, the need to fetch language data, and how image quality and language selection affect results.
Learn why downloaded CSV files show garbled characters in Excel and how to resolve encoding mismatches using a browser-based conversion tool. We also explain text import best practices to prevent missing leading zeros.
A comprehensive guide on calculating the 2026 Furusato Nozei donation limits for 2027 resident tax, detailing deduction mechanisms, input requirements, and specific tool disclaimers for salary earners in Japan.
A comprehensive guide to calculating enrollment and graduation years for Japanese resumes. Explains the unique April 1st cohort boundary, gap years, era conversions, and how to use our automatic reference timeline calculator.
We explain the basic role of simple electronic seal images in digital workflows, procedures for pasting them onto Excel or PDF documents, and how to generate transparent PNG seal images in your browser.
Learn about HEIC format compatibility and how to use our browser-based tool to batch convert your iPhone photos to JPEG or PNG. Understand the settings, conversion process limitations, and how to adjust camera preferences.
Convert phone recordings and voice memos to WAV or WebM in your browser. Learn which formats your browser can export and how to verify the result. MP3 output is unavailable.
A tool to set an open password for PDF files or unlock them with a known password. Uses RC4-128 encryption and does not support permissions restrictions or high-security AES. Explains local processing specifications and limitations.
Learn how to obscure faces, backgrounds, or license plates in your images using local browser processing. This guide explains how to use our image blurring tool and details the limitations of metadata removal and privacy protection.
Discover the essential criteria for creating secure, hard-to-guess passwords to protect your online accounts. Learn about modern security guidelines, the risks of credential stuffing, and how to use a local browser-based password generator.
Technical guide on optimizing Largest Contentful Paint (LCP) in Next.js App Router. Covers client-boundary lazy loading, next/font optimization, script prioritization, and accurate DevTools measurement workflows to mitigate render-blocking resources.
Understand browser-based image and PDF processing, external speech and data services, model downloads, local storage, and advertising or analytics requests.