Who runs CLCU Online
Md Imdadul Haque
Founder and editor, CLCU Online
CLCU Online is built and maintained by Md Imdadul Haque, who decides which calculators the site carries, which ones are removed, and how each one is explained. Messages sent through the contact page are read by Md Imdadul Haque directly.
The site has been rebuilt with a deliberate preference for fewer, better tools. Calculators that did not work properly or simply repeated another page were taken down rather than kept for the sake of a bigger number, and every remaining page explains its formula and its limits.
Why we built this
CLCU Online started from a simple frustration: too many calculator websites bury their results behind ads, registration walls, or "upgrade to see your full report" prompts. The person who needs to know their mortgage payment or check their BMI shouldn't have to create an account or sit through three pop-ups to get it.
We built CLCU Online to be the opposite of that. Every tool on this site is free, works immediately, and gives you the actual number — no friction, no bait-and-switch. We sustain the platform with unobtrusive display advertising. That's the whole model.
The site now has more than 180 calculators across finance, health, math, time and date, construction, education, and more, each with a written explanation of how it works. Every one of them follows the same principle: give people the answer they came for, as fast as possible.
What we offer
180+ Free Tools
Finance, health, math, time and date, construction, education, automotive and more, each with its own guide.
No Account Required
Use any calculator instantly. We never ask for your email, name, or any personal information to use a tool.
No Paywalls
Every tool is fully functional for free. There are no premium tiers, locked features, or results hidden behind subscriptions.
Verified Formulas
Each calculator uses a standard, published method. Pages state the formula, work through an example and note where the method stops being reliable.
Works on Any Device
Fully responsive — designed to work just as well on a phone as on a desktop. No app download required.
Regularly Updated
Where a figure changes over time, such as tax thresholds or contribution limits, pages point to the official source instead of quoting a number that could go stale.
How the calculators are built
We use standard, published formulas. Each calculator page states the formula it applies, works through at least one example by hand, and explains the assumptions and limits that matter, such as what a BMI cannot tell you or why an amortised payment is mostly interest at the start.
Calculators run entirely in your browser. Where results depend on rates or limits that change, such as tax brackets or retirement contribution caps, we link to the official source rather than quoting a figure that could be out of date.
We are not infallible. If you find a result that looks wrong, tell us through the contact page and select “Report a Calculation Error”. Reports with the inputs you used and the answer you expected are the fastest to investigate and fix.
Where we point for authoritative detail
Our guides link out to primary sources instead of paraphrasing them. Health explanations refer to the World Health Organization and the CDC. Tax and payroll explanations refer to the IRS and the Social Security Administration, and wage rules to the U.S. Department of Labor. Unit definitions follow NIST.
What our tools are — and aren't
Our calculators are designed for estimation, planning, and general reference. They are not a substitute for professional advice. A mortgage calculator gives you a useful estimate — it doesn't account for your full financial picture the way a licensed mortgage broker would. A BMI result tells you one data point about your health — it doesn't replace a conversation with your doctor.
We're clear about this throughout the site because we think honesty about what a tool can and can't do is part of what makes it genuinely useful. An estimate you understand is worth more than a precise-looking number you take at face value without knowing what it excludes.
The blog
Beyond the tools, we publish practical guides on the topics our calculators cover — how mortgage payments are actually calculated, what BMI measures and what it doesn't, how parlay bets work mathematically, and similar explainers. The goal is the same as the tools: give you a real answer instead of a vague summary.
You can read all published articles on the Blog page.
Get in touch
Found an error in a calculation? Have a suggestion for a tool we should add? Every message sent through the contact form goes to Md Imdadul Haque. We can't promise a response to every inquiry, but genuine reports of calculation errors are taken seriously and investigated promptly.
For business or partnership inquiries, use the contact form and select "Business / Partnership" as the subject — we'll get back to you within 1–2 business days.