Free Online Tools for Developers, Business & Students

Calculators, generators, and utilities that run entirely in your browser. No sign-up, no installs, always free.

93 Free Tools and Counting
Free File Conversion up to 200MB
Browse All Tools

93

Free Tools

5

Categories

100%

Free, No Sign-up

What this site is

DevBiz Tools Hub is a set of single-purpose tools for the calculations and file jobs that come up in everyday work: working out GST on an invoice, checking an EMI before signing a loan, turning a JSON export into a spreadsheet a colleague can open, or pulling the text out of a scanned page. Each tool does one thing, on one page, with no account.

Your data stays in your browser. The calculators and converters run as code on your own device, so the numbers, text, and files you work with are not uploaded. File tools handle up to 200MB. The exceptions are said plainly on their pages: the currency converter fetches the day's exchange rate (sending only the two currency codes), and the OCR tools download their recognition engine on first use. The site is free and is paid for by advertising. In the European Economic Area, the UK and Switzerland, ads follow the choices you make in Google's consent message; everywhere else, if you decline cookies in our banner, no ads are requested at all.

Pages explain their answers. Calculator pages explain how the result is worked out, and the converter pages say exactly what happens to tricky values such as leading zeros, long IDs, dates, and nested fields. The guides go deeper, and the About page explains who builds the site and why.

Popular Tools

Jump straight into one of our most-used tools.

JSON Formatter

Validate JSON and re-indent it with 2 or 4 spaces, or minify it, with the size change shown.

Developer

EMI Calculator

Calculate a loan’s monthly EMI, total interest and total repayment.

Business

CGPA / Percentage Calculator

Convert your CGPA to percentage or calculate CGPA from subject grades instantly.

Student

JSON ⇄ Excel Converter

Convert a JSON array of objects to an Excel spreadsheet, or Excel back to JSON.

Converters

Mortgage Calculator

Calculate your monthly mortgage payment, total interest, and a year-by-year amortization summary.

Finance

GST Calculator

Add or remove GST from any amount with a clear breakdown.

Business

Tool of the Day

Word Counter

Count words, characters, sentences, and estimated reading time.

Browse by Category

Developer Tools

JSON, JWT, cron, SQL, hashing and encoding utilities that run in your browser.

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Business Tools

GST, EMI, salary and break-even calculators in rupees, plus an invoice generator.

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Student Tools

CGPA and weighted-grade calculators, a word counter and a resume builder.

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Converter Tools

JSON, CSV, Excel, XML, subtitle, PDF and image conversion, up to 200MB.

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Finance Tools

US-dollar mortgage, auto loan, retirement, credit card and tax estimates.

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Featured Tools

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Word Counter

Count words, characters, sentences, and estimated reading time.

Student

QR Code Generator

Turn any text or URL into a QR code and download it as a PNG or a scalable SVG.

Developer

Salary / CTC Calculator

Estimate your approximate monthly in-hand salary from your annual CTC.

Business

Freelance Hourly Rate Calculator

Calculate the hourly rate you need to hit your target annual income.

Business

Cron Expression Generator & Parser

Build a cron expression from a simple form, or parse one into plain English.

Developer

Hash Generator (MD5, SHA-1, SHA-256)

Generate MD5, SHA-1, and SHA-256 hashes from any text as you type.

Developer

JSON ⇄ CSV Converter

Convert a JSON array of objects to CSV rows, or CSV back to JSON.

Converters

CSV ⇄ Excel Converter

Convert CSV files to Excel spreadsheets, or Excel workbooks back to CSV.

Converters

Markdown ⇄ HTML Converter

Convert Markdown to clean HTML, or HTML back into readable Markdown.

Converters

SRT ⇄ VTT Converter

Convert SubRip (.srt) subtitles to WebVTT, or VTT back to SRT.

Converters

ZIP Extractor

Open a .zip archive in your browser and download the files you need, one at a time.

Converters

Image Format Converter

Convert images between PNG, JPG, WebP, BMP, and GIF right in your browser.

Converters

Image Compressor

Compress JPG, PNG, or WebP images with an adjustable quality slider.

Converters

Merge PDF Files

Combine multiple PDF files into one, in the order you choose.

Converters

Image to Text (OCR)

Extract text from a photo, scan, or screenshot using on-device OCR.

Converters

Color Palette Generator

Generate harmonious color palettes with 5 harmony types, per-color locking, and CSS/Tailwind/JSON export.

Developer

Text Diff Checker

Paste two texts and see word-level or line-level differences highlighted.

Developer

JSON to TypeScript Interface Generator

Paste JSON to generate a TypeScript interface or type, with optional fields and naming control.

Developer

SQL Query Formatter

Paste unformatted SQL and get clean, properly indented output.

Developer

Advanced Home Loan Calculator

Calculate EMI with prepayment simulation, multi-rate comparison, and a monthly or yearly schedule.

Business

Time Zone Converter

Convert a date and time from one time zone to another.

Converters

Investment Compound Interest Calculator

Project investment growth with compound interest and optional monthly contributions, with a growth chart.

Finance

Latest from the Blog

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business

Why Your In-Hand Salary Is Lower Than Your CTC

A line-by-line breakdown of an ₹8 lakh CTC showing where the money goes (employer PF, your own PF, professional tax, and TDS), plus the PF wage-ceiling detail that can change your in-hand pay by thousands a month.

business

How to Calculate Home Loan EMI and Reduce Total Interest

A worked ₹40 lakh example showing where your EMI goes, and what a shorter tenure, a lower rate, and prepayments each save in rupees.

business

How to Write an Invoice That Gets You Paid Faster

The fields a GST invoice must carry, how to write payment terms a client's accounts team can act on, and the MSME 45-day rule small suppliers in India should know about.