About raatools/

What this site is

raatools/ is a collection of single-purpose tools — a resistor colour code decoder, a pace calculator, a PDF merger, a chemical equation balancer, a subnet calculator, and around 130 others. Each one does one job, loads in under a second, and needs nothing from you: no account, no email address, no free trial that turns into a subscription.

The tools are grouped into 26 categories, from electronics and physics through to cooking and SDR radio. You can browse them all from the tools index.

Why it exists

Most of these calculations already exist online, and most of the sites hosting them are miserable to use. You search for "LED resistor calculator", land on a page that asks you to accept forty tracking vendors, scroll past three paragraphs of keyword filler, and find an input box that reloads the whole page every time you change a number. Then the answer arrives with no explanation of where it came from.

raatools/ started because I kept needing these calculations while working on electronics projects and kept resenting the tools I had to use to get them. The design goal is narrow: land on the page, get the number, understand why it's that number, leave. Every tool page carries a written explanation of the underlying formula and a worked example, because a calculator that gives you a number without teaching you anything is a calculator you have to come back to forever.

Who makes it

raatools/ is built and maintained by Andreas, a developer based in Norway. It is operated by Raadig AS (organisation number NO 833 209 132), a Norwegian registered company.

The subject matter follows what I actually work on. The electronics and homelab tools came out of building things on a bench with a multimeter next to me; the self-hosting and Raspberry Pi material came from running my own servers. Where a tool covers ground I know less well — the chemistry and astronomy sections, for instance — the formulas are taken from standard references and the working is shown on the page so you can check it rather than trust it.

If you find a tool that returns a wrong answer, I want to know. That is the single most useful message you can send me, and it goes straight to the top of the list. Get in touch here.

How the tools work

Almost everything on raatools/ runs as JavaScript in your own browser. When you merge two PDFs or compress an image here, the file never travels anywhere — it is read by your browser, processed on your device, and handed back to you. Nothing is uploaded, nothing is stored on a server, and nothing is retained after you close the tab.

This is not a promise about how carefully we handle your data. It is an architectural fact: there is no server-side file handling to trust, because there is no server-side file handling. You can verify it by opening your browser's network tab while you use any of the file tools.

A small number of tools genuinely cannot work this way. A WHOIS lookup, a DNS query, an SSL certificate check or a currency conversion has to ask something on the internet. Those tools send the minimum required — the domain you typed, or nothing but the request itself — and the privacy policy names each of them.

How the site is funded

raatools/ carries advertising. That is the whole business model: the tools stay free and account-free, and the ads pay for the servers and the time.

The trade-off I have tried to hold is that ads go on pages that have earned them — a tool with a real explanation attached — and that no tool is degraded, rate-limited, or held back behind a "pro" tier to make advertising more attractive. There is no premium version of raatools/ and there is no plan for one. Ad and cookie behaviour is described in full in the privacy policy.

How it's built

The site is a SvelteKit application, prerendered to static HTML and served by nginx from a server in Norway. Every page is available in English, Norwegian, French, German, Spanish, Finnish and Ukrainian. There is no tracking beyond aggregate analytics, no A/B testing framework, and no third-party JavaScript other than the ad script.

Accessibility is a stated target rather than a finished job — raatools/ aims at WCAG 2.2 Level AA, and the current state, including the parts that fall short, is documented in the accessibility statement.

What's next

The current focus is depth rather than count: better explanations on the tools that already exist, and written guides covering the subjects behind them. New tools get added when I need one and it doesn't exist yet, which is generally how the existing ones came about.

Contact

Bug reports, corrections, tool suggestions and anything else: mail@raadig.no, or see the contact page for company details and what to expect.