LibraireStudios is a suite of twelve free online tools built to help people with the everyday calculations that come up in real life — working out whether a new appliance will push the electricity bill up, figuring out how many working days until a deadline, scaling a recipe for more guests, or generating a QR code without downloading an app.
Every tool on this site works directly in your browser. There is no account to create, no data sent to a server, and no software to install. Results appear instantly, and the tools work just as well on a phone as on a desktop.
Watt Wise calculates appliance running costs. Budget Wise breaks a monthly household budget into categories. Goal Saver shows what to save each month to hit a target by a set date.
For home projects, Decortastic estimates paint and wallpaper. Mile Minder calculates journey fuel costs. Unit Switch converts metric and imperial measurements.
Daily tools: Quick QR, Anagram Solver, Figure It (percentages and VAT), Recipe Right, Workday Count, and Datefully.
All calculations run locally in the browser using JavaScript. Nothing is sent to any server. Pages are designed to load quickly on slower mobile connections and work without an internet connection once open.
The design is intentionally simple: plain inputs, clear labels, results that are easy to read and share. No pop-ups, no dark patterns.
Alongside the tools, LibraireStudios publishes a growing collection of practical guides covering the maths behind everyday tasks in plain language — how electricity bills are calculated, how to build a household budget, how metric and imperial units relate, and more.
All twelve tools are also available as a free Android app — Libraire — with saved results, folders, and offline access to the guides. Available on Google Play from RapidIDApps.
LibraireStudios is made by RapidIDApps, an independent software developer based in the United Kingdom. It is a solo project, built and maintained by one person. Updates and new tools appear when genuinely ready, and feedback from real users directly influences what gets built next.
The site launched with a focus on financial and household tools — areas where a quick, reliable calculation is often replaced by a guess. The aim is to make that calculation available in a few taps, on whatever device is to hand, without friction.
Yes, all twelve tools are completely free to use. There is no account, no trial period and no premium tier for the web tools.
No data is sent to any server. All calculations happen in your browser. If you close the page, your inputs are gone — nothing is retained.
Yes. The tools are designed to work well on mobile. The Libraire Android app also provides offline access to all twelve tools.
Each tool has a Contact link at the bottom of its page. Feedback is read and genuinely considered.
RapidIDApps is the independent developer behind LibraireStudios and the Libraire Android app, based in the United Kingdom.
