About Toolbase
Toolbase is a free collection of web tools for those moments when you think "I wish I had a tool for this" — at work, in study, or in daily life.
Every tool is completely free with no account or sign-up required.
Tool Categories
Tools are organized into 19 categories.
Crypto 19
Free hash functions (MD5, SHA-256, Argon2), bcrypt password verification, and secure password generation, plus classical cipher tools like Caesar, Vigenère, and Enigma. Handy for development, learning, and security testing.
Developer Tools 83
Free developer tools: JSON and CSV formatting and conversion, Base64, JWT verification, number bases, cron expressions, and SEO tag validation.
Text 24
Free text tools: character counting, naming convention conversion, slang and dialect converters, emoji and fancy fonts, Morse code, QR code generation, and Chinese calligraphy font generation.
Math 48
Free calculation tools ranging from a calculator, sales tax, BMI, and compound interest, to function graphs, sequences, prime checks, pie charts, geometry, probability and expected values, Fourier series visualisation, and size/unit conversions like shoe and ring sizes.
Date/Time 35
Free date and time tools: world clock, timer, stopwatch, Japanese holidays, rokuyo, and era calendar, age and yakudoshi calculators, plus date difference, business day, and countdown calculators.
Design 33
Free design tools for converting between color code formats such as RGB, HEX, and HSL, generating CSS gradients and shadows, converting image formats and calculating aspect ratios, generating favicons in multiple sizes, plus paper size reference charts and dummy sample PDF generation.
Network 33
Free network tools for URL encoding and a REST API tester, IP address and domain WHOIS lookups, bandwidth and port reference tables, plus DKIM, DMARC, and SSL certificate checks for email and domain security.
Money 154
Free money calculators for take-home pay, furusato nozei (hometown tax) donations, loans, and investment simulations, plus lottery and gambling odds and expected-value calculators.
Business 61
Free calculators for SaaS and startup metrics, the creator economy, and business management — from MRR/ARR to marketing and project metrics.
File Operations 12
Free file tools: ZIP and TAR.GZ compression and extraction, image-to-PDF conversion, PDF organising, compression, rasterising, redaction, and watermarking, and CSV encoding repair.
Chemistry 11
Free chemistry calculators for study and practical work: molecular weight, pH, the ideal gas law, the periodic table, and more.
Physics 16
Free physics calculators, from mechanics to Ohm’s law, resistance networks, and component colour codes — for study and for electronics work.
Data 17
Free reference lookups for postal codes, municipalities, bank codes, country codes, airport codes, and port codes.
Music 10
Free tools for musicians: metronome, tuner, circle of fifths, capo chart, and chord progressions — for practice and for theory.
Media 11
Free browser tests for camera, microphone, and speakers, plus dead pixel, keyboard, reaction time, colour vision, and hearing tests.
Health 16
Free health tools: BMR, calories, and body fat calculators, running pace, sleep timing, pregnancy dates, and a health checkup reference.
Hardware & Standards 4
A free reference collection for quickly comparing hardware standards such as LAN cables, Wi-Fi, and USB.
Daily Life 13
Free everyday tools: travel time and fuel cost, an atmosphere layer visualiser, pet age/body condition/feeding calculators, a concrete quantity calculator, a cups-to-grams converter, and a personal carbon footprint estimator.
Games & Events 1
Free tools for running tournaments and events: build a tournament bracket from a list of names, record who advances, and save or print the result.
Tool Page Layout
Tool pages are made up of the sections below. Sections with nothing meaningful to say are omitted on a per-tool basis.
Meet Tool-kun (ツールくん)
The Toolbase mascot
- NameTool-kun
- RoleOfficial Toolbase mascot & apprentice tool builder
- HobbiesBuilding tools, sharing trivia
- Special skillDigging up facts nobody knew they needed
- Catchphrase"That can be automated."
- TraitEyes always darting around, scanning everything for the next tool idea
- DreamTo make every tiny annoying task in the world disappear
Tool-kun quietly shows up across Toolbase — and yes, he's the one writing those "Side Note" trivia sections. He gets a little too excited once he starts researching, which is why the articles sometimes run long. The reason he's always looking upward in the footer? He's thinking up the next tool idea.
Who runs Toolbase
Toolbase is planned, built, and operated by the company below. Some of our tools perform calculations governed by law, such as taxes and social insurance contributions, so we state plainly who is responsible for them.
| Legal name | Codebase Inc. (株式会社コードベース) |
|---|---|
| Address | THE CASK GOTANDA 902, 2-5-2 Higashi-Gotanda, Shinagawa-ku, Tokyo 141-0022, Japan |
| Founded | October 20, 2017 |
| Representative | Seiya Tajikara (田力 誠也), Representative Director |
| Business | Software development and cloud services |
Editorial policy
Because we publish calculations that rest on tax law and social insurance rules, we decided in advance how figures are sourced and maintained. Setting out how the site is built should give you something concrete to check it against.
- Statutory figures are taken from primary sources
- Tax rates, insurance contribution rates and deduction amounts are entered only after consulting the primary material published by the responsible ministry or public body, and each tool page shows the source and the period it applies to. Explainer sites and aggregators are never cited as the source.
- Figures we cannot verify are left blank rather than guessed
- Where a primary source could not confirm a value, we leave it unregistered instead of filling in something plausible. A missing figure is safer than a confident wrong one.
- Expiry of applicable periods is checked automatically
- Every registered figure carries the period it applies to, and an automated check flags the ones approaching expiry so they get revisited. The aim is to avoid the situation where a rule changes and nobody notices.
- Public datasets are refreshed monthly
- Bank codes, municipalities and postal codes are pulled in automatically each month, following the publication schedule of the bodies that maintain them.
- Each page shows when it was last updated
- The date a tool was last revised appears near the top of its page, so you can judge how current the information is for yourself.
- We welcome corrections
- If you spot an error in a figure or an explanation, please tell us through the feedback form. We check it and fix it.
- This is not a substitute for professional advice
- Results are estimates. For anything that turns on individual circumstances, such as a tax liability or a benefit entitlement, please confirm with the relevant authority or a qualified professional before acting on it.
We'd love your feedback
"I wish there was a tool for this." "This part is hard to use." "I found a bug." — all input is welcome. Your feedback directly shapes what we build next.
Send feedback