Tools that stay out of your way.
CalcuOnline is a growing suite of precise, private, browser-based instruments for finance, business, mortgages, insurance, real estate and construction, health, developer work, PDF/file conversion, and student essentials — built and maintained by a small, focused engineering team.
What CalcuOnline is
CalcuOnline started as an internal tool kit — a place to keep the financial and engineering calculations that came up repeatedly while building eInvit. EMI estimates for event budgets, material quantities for venue work, unit conversions, tax figures. They kept getting rebuilt from scratch in spreadsheets.
Rather than keep them private, we turned them into a public site — free to use, no account required, with enough depth (charts, schedules, PDF export, live currency rates) to be genuinely useful beyond a quick Google search. What began as a handful of loan and tax calculators has grown into a 11-category suite covering finance and investing, business documents and metrics, mortgages, insurance, real estate and civil engineering, health and clinical reference numbers, developer utilities, PDF and file conversion, writing tools, and student essentials for the Indian education system.
Every tool is a single-page web app that computes entirely in your browser. Nothing you type is transmitted, stored, or logged by us — including the PDF and file tools, which use WebAssembly and the Canvas API to compress, merge, split, and convert files on your own device rather than a server.
Tony Augustine Labs
CalcuOnline is designed, engineered, and maintained by Tony Augustine, founder and product owner at Tony Augustine Labs (TAL), an independent software studio based in Kerala, India, building wedding-tech and productivity tools for South Asian markets.
TAL’s flagship product is eInvit, a digital invitation platform for Indian weddings and events — RSVP tracking, guest management, WhatsApp reminders, QR check-in, gift registries, and a themed Card Studio with nine invitation layouts. CalcuOnline is developed and maintained as a free companion utility alongside it.
As a small, focused team, we hold every one of our 93+ tools to the same standard: verified formulas, careful engineering, and regular upkeep as requirements — tax slabs, mortgage insurance premiums, contribution limits — change year to year. Full portfolio and studio details are available at tony-labs.vercel.app. If you spot an error in a calculation or a design issue, we want to know — get in touch.
Our values
Every calculation runs locally in your browser. Nothing you type is sent to any server we control. The only external calls are the live exchange-rate fetch (from a public CDN) and the anonymous visitor counter.
Results update in real time as you type — no submit button, no loading spinner, no round trip to a server. Speed is a feature.
Every formula is documented in the tool. We use standard financial and engineering formulas and show our working, so you can verify results against any textbook or spreadsheet.
Finance tools export results to PDF and CSV, so you can drop the output directly into a report or share it with a colleague.
CalcuOnline is free to keep free through minimal, clearly-labelled ad placements that never sit inside a calculator or block a result — plus a cookie consent choice on your first visit. We build this as a companion to our main product, eInvit, and our incentive is quality, not page views.
Currency selectors on all finance tools, 40+ currencies in the converter, and unit systems chosen to cover the most common engineering standards worldwide.
Roadmap
CalcuOnline is actively developed. Planned additions include:
- →2013 ASCVD (Pooled Cohort Equations) cardiovascular risk calculator, once the race/sex-specific coefficients are verified against the primary source
- →Cron expression builder and explainer
- →Structural beam load calculator for civil engineers
- →Savings/CD interest calculator with tax-on-interest breakdown
- →Unit price & bulk-buy comparison calculator
- →More Indian state-specific stamp duty and registration calculators
Have a specific tool you need? Request it here.
Planning a wedding or event?
eInvit — our digital invitation platform for Indian weddings and events. RSVP tracking, WhatsApp reminders, gift registries. Free to start.
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