Every calculator
you actually need.
14 free online calculators built for India — income tax, SIP, EMI, GST, salary, YouTube, and more. No login. Instant results.
India Financial Calculators
Our most-used tools cover the financial decisions every Indian salaried professional faces. The Income Tax Calculator handles both old and new tax regimes with the correct FY 2024-25 slabs, Section 87A rebate, and standard deduction. The SIP Calculator shows how monthly investments compound over time using the standard FV formula — great for planning mutual fund goals. The EMI Calculator covers home loans, car loans, and personal loans with full principal vs interest breakdowns. The GST Calculator handles both adding tax (for sellers) and removing it (reverse calculation for buyers), with automatic CGST/SGST split. The Salary Calculator converts CTC to take-home pay showing PF, HRA, and special allowance breakups.
Creator Economy Calculators
The YouTube Earnings Calculator estimates AdSense revenue from monthly views, RPM, and monetized playback percentage — plus a sponsorship income estimate. The Instagram Earnings Calculator models per-post rates based on follower count, engagement rate, and content niche (finance, tech, lifestyle, fashion, food, health), giving monthly and annual income projections.
Investment & Trading Tools
The Stock Average Calculator computes the weighted average cost per share across multiple buy orders at different prices and quantities — essential for traders who average down during dips. It also shows unrealised P&L at any current market price. The Mortgage Calculator goes beyond EMI: it produces a full year-by-year amortization schedule showing exactly how much of each year's payments go to principal vs interest, plus property tax and insurance in the total monthly cost.
Tech & Utility Calculators
The OpenAI API Cost Calculator helps developers estimate per-request, daily, and monthly spend across GPT-4o, GPT-4o mini, o1, and other models — useful for budgeting AI features in production apps. The Currency Converter fetches live mid-market rates from Yahoo Finance (with automatic fallbacks) for 150+ currencies. The Word Count Calculator instantly counts words, characters, sentences, paragraphs, and reading/speaking time — useful for writers, students, and content creators. The BMI Calculator covers both WHO standard and WHO Asia-Pacific cut-offs, which are stricter for Indian populations. The Age Calculator gives exact age in years, months, and days along with zodiac sign and days to next birthday.
About CalzHub
CalzHub is a free calculator platform built specifically for Indian users and creators. Every tool is designed to answer a real question — from "how much tax will I pay this year?" to "how much can I earn with 100K YouTube subscribers?" — with accurate, up-to-date formulas and a clean interface that works on any device.
Accuracy first. Tax calculators are updated for each financial year using official CBDT notifications. Financial calculators use standard actuarial and banking formulas. Creator income estimators are calibrated against publicly reported niche RPM benchmarks. Where calculations involve estimates (YouTube RPM, Instagram rates), we show the underlying assumptions so you can adjust them to your situation.
Privacy by design. No account is needed. Numbers you enter are computed server-side and immediately discarded. We do not store, sell, or share any data you input into a calculator.
Free, forever. CalzHub is supported by Google AdSense. Ads are clearly labelled and do not affect calculator results. You can use every tool without creating an account, without giving us an email, and without paying anything.
Frequently Asked Questions
Are all CalzHub calculators free to use?▼
Yes, every calculator on CalzHub is completely free with no login, no subscription, and no hidden charges. The site is supported by Google AdSense ads, which allows us to keep all tools free for everyone.
How accurate are the calculations?▼
Our calculators use the official formulas published by the Government of India for tax, GST, and PF calculations. Financial calculators (SIP, EMI, mortgage) use standard compound interest formulas. We update tax slabs and rates each financial year. For legal or investment decisions, always verify with a qualified professional.
Do you store any personal data I enter?▼
No personal data is stored. Numbers you enter (income, loan amount, date of birth, etc.) are sent to our server to compute the result and immediately discarded — we do not save, log, or share any calculation inputs. Anonymous pageview analytics are collected for site improvement.
Which calculators are available on CalzHub?▼
CalzHub offers 14 calculators: Income Tax (India FY 2024-25), SIP returns, EMI for loans, GST add/remove, CTC to in-hand salary, YouTube earnings, Instagram influencer income, stock average price, OpenAI API cost, age from date of birth, BMI, mortgage payment with amortization, word count, and live currency converter.
Can I use CalzHub on mobile?▼
Yes. CalzHub is fully responsive and works on all screen sizes. It is also a Progressive Web App (PWA) — you can add it to your home screen on Android or iOS for an app-like experience with offline access to previously visited pages.
Are the income tax calculations updated for FY 2024-25?▼
Yes. Our income tax calculator reflects the Union Budget 2024 changes including the revised standard deduction of ₹75,000 for salaried employees under the new regime, updated tax slabs, and the Section 87A rebate (zero tax for taxable income up to ₹7 lakh under the new regime).