We Build Tools You Can Actually Trust

Our Mission

Most online tool sites are frustrating. They're slow, packed with intrusive ads, copy-pasted from each other, and rarely explain how the result was computed. They treat the visitor as a click to monetize, not a person to help.

We started HT99 Tools to prove the opposite is possible. Every tool here is hand-coded against authoritative sources — official documentation, peer-reviewed equations, government publications, IETF RFCs, NIST standards. Every page explains how the math works, shows the formula, walks through a real example, and honestly lists the limitations. We don't pretend a calculator is financial advice. We don't bury the answer under six ad slots. We treat each tool like a piece of editorial work.

The result is a site you can bookmark, share with colleagues, recommend to students, and trust for everyday decisions — from checking a loan EMI to validating a JSON payload.

What We Build

Our catalog spans 10 categories and 118+ individual tools:

• Finance Calculators: Loans, mortgages, investments, taxes — built with verified formulas from official sources.
• Health & Fitness: BMI, BMR, calorie, body composition — using CDC, WHO, and peer-reviewed formulas.
• Math Calculators: Algebra, geometry, statistics — with formulas shown and step-by-step examples.
• Unit Converters: Length, weight, temperature, data storage, currency — accurate to 8 decimal places.
• Text & SEO Tools: Word counters, case converters, readability checkers — privacy-first, runs in browser.
• Developer Tools: JSON, Base64, regex, JWT, hashes — per IETF RFCs and NIST standards.
• Generators: Password, UUID, QR codes, gradients — using cryptographically secure RNG where it matters.
• Time & Date: Age, date difference, time zones, countdowns — handles edge cases like leap years.
• Color & Design: HEX, RGB, HSL, WCAG contrast — with the exact W3C relative luminance formula.
• Everyday Utilities: Tips, fuel cost, dice, GPA — practical tools for daily life.

We also publish 31+ in-depth explainers that complement the tools — covering the why and when, not just the how.

Editorial Standards

Every page on this site follows the same publishing checklist:

1. Accuracy review — formulas are checked against primary sources. When a source exists, we link to it.
2. Methodology transparency — the formula or algorithm appears on the page, with a worked numerical example, so you can verify the output yourself.
3. Honest limitations — every tool page lists what it does not do. A BMI calculator will not diagnose obesity. A loan calculator will not predict your bank's final offer. We say so plainly.
4. Accessibility — keyboard-friendly, screen-reader friendly, mobile-first, no intrusive pop-ups, body text sized at 16px minimum, color contrast checked against WCAG 2.2 AA.
5. Privacy — most tools run entirely in your browser. Your inputs are never sent to our server. We do not store, log, or resell your data.

Who's Behind HT99 Tools

HT99 Tools is run by a small editorial team of engineers, finance enthusiasts and writers. The team is intentionally multidisciplinary because no single discipline covers the breadth of tools we publish — a tax calculator needs a finance eye, a regex tester needs an engineering eye, and a BMI explainer needs a health-science eye.

Every article is dated and tagged with a "last updated" stamp that reflects the most recent material edit (we never bump a date without a real change). Articles are reviewed at least once a year for accuracy, and re-reviewed whenever a cited source is updated. If you find a mistake — please email us and we will fix it, publicly.

How We Make Money

HT99 Tools is free to use and always will be. We cover hosting and editorial costs through occasional, non-intrusive display advertising (placed only outside the tool area, never inside the interface). We do not sell user data. We do not accept paid placements or sponsored tool rankings. We do not use affiliate links without clear disclosure.

If you'd like to support us without ads, the simplest thing you can do is share a tool you found useful with someone who needs it.

Get in Touch

Questions, bug reports, feature requests, corrections — we welcome all of them. Email us at contact@ht99.icu or use our contact form. We respond within 1–2 business days.

Site Information

Domain	https://ht99.icu
Contact email	contact@ht99.icu
Founded	2024
Tools available	118+
Articles published	31+
Privacy policy	View here
Terms of service	View here