About ToolNest
ToolNest is a library of 169 free, no-signup tools and 15 plain-English guides — calculators, converters, formatters and generators that run entirely in your browser.
How our calculators are built
Every calculator implements the published formula or statutory rule for what it computes — not an approximation of a competitor's output. Each tool page explains its method in the “How to use” and FAQ sections, so you can check our working.
- Indian tax & savings tools(income tax, salary, PPF, EPF, NPS, gratuity, HRA, GST) follow the rules published by the Income Tax Department, EPFO and the Ministry of Finance, including the current financial year's slabs, rebates and scheme interest rates.
- Loan and investment tools (EMI, SIP, FD, CAGR…) use the standard reducing-balance and compound-growth formulas used by banks and fund houses.
- Developer tools (JSON, XML, Base64, JWT, regex…) use the relevant specifications (RFC 4180, RFC 4648, RFC 7519 and friends).
Kept current, on purpose
Tax slabs, rebate limits and small-savings interest rates change — often every year, sometimes every quarter. Tools whose rules can go stale carry a visible “updated” date on the page, and we review rule-dependent calculators when the rules change (e.g. after each Union Budget and quarterly small-savings rate announcements). If you spot a figure that has changed before we have, we want to know.
Privacy: everything runs in your browser
None of your inputs — not your salary, your loan amount, your JSON, your passwords — are ever sent to a server. Every tool computes locally with JavaScript in your browser. Close the tab and it's gone.
What our results are (and aren't)
Calculator results are estimates for information and planning. They are not financial, tax or legal advice, and they can't account for your full personal situation — for decisions involving real money, confirm with a qualified professional or the official source.
Contact
Found a bug, an outdated rate, or want a tool we don't have yet? Email us at toolnest.app13@gmail.com or use our contact form — corrections are prioritised.