About Cubestack

Cubestack is a free collection of everyday online tools: a PDF editor, image compressor, exam photo resizer, income tax and EMI calculators, a GST invoice maker, a resume builder, typing tools for Indian languages and many more. The idea is simple: the small jobs people do every day should take seconds, without installing an app, creating an account or uploading private files to a stranger's server.

How the tools work

• On your device. Most tools run entirely in your web browser. When you compress an image or edit a PDF, the file is processed on your phone or computer and is never uploaded to us.
• No signup needed. Every tool works without an account. A free account only lets you save favourite tools.
• Free to use. There are no paid plans or usage limits. The site is supported by advertising.
• Works offline. Cubestack can be installed as an app, and tools you have opened before keep working without an internet connection.

Who it is for

Students preparing exam applications, job seekers writing a resume, small businesses making GST invoices, salaried people planning their taxes, developers who need a quick JSON formatter, and anyone who just needs to merge two PDFs. Many tools are built around Indian needs: exam photo and signature sizes, Indian tax rules, rupee formatting, and typing in Hindi, Tamil and Kannada.

What you will find here

• Text & Writing (25 tools): Resume, typing, Hindi & Tamil, word count.
• Image & Media (17 tools): Exam photo, passport photo, compress, QR.
• PDF Tools (14 tools): Edit, compress, merge, split, protect.
• Developer (21 tools): JSON, Base64, hash, JWT & more.
• Calculators (37 tools): Scientific, fractions, age, GST, units & science.
• Health & Fitness (8 tools): Calories, BMI, pregnancy, sleep, water.
• Everyday & Devices (13 tools): Timers, random numbers, mic, webcam & keyboard tests.
• Security (5 tools): Passwords, hashing, UUID.
• SEO & Web (11 tools): Meta, OG, robots, sitemap, DNS.
• Money & Tax (16 tools): Income tax, salary, SIP, FD, GST invoice.

Accuracy

Calculators follow published formulas and the current rules they name, such as the income tax slabs for the stated financial year. We check them against official sources and correct them when rules change. Results are for guidance only: for tax, medical or legal decisions, confirm with a qualified professional.

Get in touch

Found a bug, need a tool we don't have yet, or spotted a wrong number? Email contact@cubestack.in or see the Contact page. Please also read our Privacy Policy and Terms of Service.