James Graham

Over the course of my career, I have helped over 20 million people worldwide through free resource websites. There is a quote by Robert Ingersoll that has always resonated with me: "We rise by lifting others." That idea sits at the centre of everything I have built.

You came here with a question. That is why this exists.

Maybe you are a first home buyer trying to figure out what you can actually afford. Maybe you are staring at a tax return wondering what PAYE really means for your take-home pay. Maybe you just need a straight answer about GST, KiwiSaver, or how much your student loan repayments will be, and you do not want to pay someone to tell you.

That is exactly why Calculate.co.nz was built. Not as a business pitch. Not as a side hustle. As a belief, held for over fifteen years, that the information people need to make good financial decisions should be free, accurate, and available to everyone.

My name is James Graham. I am a data and analytics professional by day and a builder of free tools by night, and I have spent the better part of two decades trying to make financial knowledge more accessible in New Zealand. Every calculator, every guide, every page on this site exists because someone, somewhere, typed a question into a search engine and deserved a clear answer without a paywall, a sales funnel, or a catch.

Where it started

In 2009, New Zealand was in the grip of the global financial crisis. Opportunities were scarce, and for a lot of people it was difficult to see a way forward. That year, I enrolled in Trade and Enterprise New Zealand's "Be Your Own Boss" programme, a free three month course designed to help people develop a viable business case and get started on their own terms. For those who demonstrated a strong enough plan, there was a small financial grant available at the end. I completed the course and was awarded one of the two grants.

It is worth pausing on that for a moment. A free government programme, run during the worst economic conditions in a generation, gave someone the structure, the confidence, and just enough financial backing to get started. I had been tinkering with websites since the early 2000s, but that course gave shape to the idea that I could build something useful at scale. It is a powerful example of how something relatively simple, a three month course and a modest grant, can fundamentally change the trajectory of a person's life when the infrastructure and the societal ladder are there to climb. That investment by Trade and Enterprise New Zealand has been repaid many times over through the taxation contributions I have made to this country in the years since, and through the millions of people the tools I built have gone on to help for free.

My first attempt at client web design taught me something important fast: I did not want to build things for clients. I wanted to build things for people. There is a difference. Clients want revisions. People want answers.

I noticed that New Zealanders were constantly searching for calculation tools online, and that most of what they found was either outdated, inaccurate, or buried behind advertising that made the experience miserable. So I started building. The first calculator, a GST tool launched in 2011, reached the number one spot on Google within weeks. It was simple, it was fast, and it gave people what they needed without asking for anything in return.

Finding an edge in a market full of giants

In those early days, I was competing against established companies with significant budgets. I could not outspend them. So I outworked them. I developed a strategy built on patience and precision: targeting narrow gaps that bigger players ignored, acquiring strong domain names that matched exactly what people were searching for, and building tools that worked better than anything else available at the time.

One successful calculator became ten. Ten became fifty. Fifty became over one hundred and fifty individual websites, each solving a specific problem for a specific group of people. At one point, I was ranked among the top ten Google Publishers in New Zealand, not through spending, but through relentless attention to what people actually needed. Every one of those sites was free to use. That was never a compromise. It was the entire point.

From 150 sites to one platform

As the web evolved, managing over one hundred and fifty standalone sites became unsustainable. Maintaining top rankings, keeping content accurate, and delivering a consistent experience across that many properties was taking more energy than building new tools. I saw the opportunity to do something better: bring everything together under one roof.

That vision became Calculate.co.nz. A single, purpose-built platform that transformed scattered resources into a unified experience. Instead of dozens of separate calculators living on separate domains, users could now find everything in one place: mortgages, tax, KiwiSaver, lending, budgeting, investment, and more. All free. All designed for the New Zealand market. All held to a standard where accuracy is not negotiable. One site to bookmark. One place to trust.

Building tools that changed conversations

Along the way, several projects took on a life of their own. PropertyPrice.co.nz brought property price transparency to the New Zealand market at a time when that information was difficult to access. Over 400,000 people used it. It changed the way everyday Kiwis could understand what was happening in their own neighbourhoods.

Salary.co.nz exposed remuneration ranges across more than 200,000 roles, giving job seekers in New Zealand and Australia something they had never had before: a clear picture of what their work was worth. The dataset was strong enough that a prominent New Zealand business figure reached out, recognising its value. I chose not to sell. The tool was built for the people using it, not for someone else's commercial gain. That principle has guided every decision. If a project does not serve the people it was made for, it does not ship.

What drives this work

I am, by most measures, deeply introverted. I have turned down television and radio opportunities across the years because the spotlight has never been the point. The point is the person sitting at their kitchen table at 10pm trying to figure out whether they can afford their first home. The point is the small business owner running the numbers on GST for the first time. The point is the parent checking whether their KiwiSaver is actually on track.

At university I completed majors in Human Geography and Social Anthropology, so I have always been fascinated by people and what contributes to their respective structure and agency within their lives. That academic grounding reinforced something I keep coming back to: sometimes something small can make a big difference. A free calculator. A clear guide. A straightforward answer at the right moment. Those moments are where this work lives. Quietly. Consistently. For over fifteen years.

What you will find here

Calculate.co.nz now houses more than 1,604 free calculators and over 278 financial literacy guides, covering everything from PAYE and GST through to mortgage comparisons, KiwiSaver projections, retirement planning, student loans, and investment analysis. Every tool is designed with two principles: simplicity and accuracy.

The calculators are built specifically for the New Zealand market, using current rates and legislation. The guides are written to be understood by anyone, regardless of financial background. No jargon walls. No assumptions about what you already know. You can read exactly how the tools are built in our editorial standards, and how the numbers are kept current in how we keep data current.

The site is also part of a broader family of resources. In 2023, I launched Realtor.co.nz with what is now a dedicated team of fifteen. Realtor.co.nz is a New Zealand property transaction literacy website. Whether you are buying, selling, or building property in New Zealand, it breaks the complicated parts of the property process down into manageable steps. My own experience building a home in Canterbury fed directly into the platform's Builder Guide, ensuring it contained real, practical, firsthand knowledge rather than generic advice.

Calculate.co.nz has also been the primary calculation and tool partner of interest.co.nz for seven years. Interest.co.nz is one of New Zealand's most established and trusted sources of financial information and analysis, and over that time our calculators have powered many of the tools its readers use to work through mortgages, savings and everyday money questions. It is a partnership built on the same standard that guides everything here: figures that are accurate, current and genuinely useful.

How I review and maintain these tools

Accuracy is not a one-off task, it is a routine. I personally review and maintain the calculators and guides on this site, and the process is deliberately boring, because boring is what keeps figures right. Every calculator is built from scratch against primary New Zealand sources, never copied from another site, and verified against a worked example so the formula and the published result agree. Shared rates and thresholds live in central data files, so a figure like the GST rate or an ACC levy is defined once and flows to every tool that uses it, which removes the risk of one calculator being updated while another is missed.

Sources are checked on a twice-monthly cycle against Inland Revenue (IRD), the Reserve Bank of New Zealand (RBNZ), Stats NZ, the Ministry of Social Development and Waka Kotahi, and tools are updated whenever a rate or rule changes. Automated checks run across the whole library to catch broken logic, missing structured data or stale figures. You can read the full method in our editorial standards and in how we keep data current. If you ever find an error, tell me and it gets fixed promptly.

My background sits behind this work: more than fifteen years building free New Zealand financial tools since the first GST calculator in 2011, a working career as a data and analytics professional, and university majors in Human Geography and Social Anthropology. That mix is deliberate. The analytics side keeps the numbers honest, and the social-science side is a constant reminder that behind every calculation is a real person making a real decision.

The promise

Everything on this site is free, and it will stay that way. The commitment I made fifteen years ago, that access to clear financial knowledge should never depend on what someone can afford, is the same commitment that guides every new calculator, every new guide, and every update published here today.

I work on Calculate.co.nz from a small village in Canterbury. The team that supports the broader vision spans continents. The ambition is not small. But the purpose is simple: help people make better decisions by giving them the tools and information to do so, and never charge them for it.

If Calculate.co.nz has helped you answer a question, plan a decision, or feel a little more confident about your finances, then it is doing exactly what it was built to do.

Get in touch

If you have found an error, have a question, or would like to suggest a tool, please contact us. You can also connect with me on LinkedIn. Calculate.co.nz is part of the Realtor.co.nz group.