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Nithish

Nithish

Developer & Blogger , 21K Tools
India
34 Published Posts

About Nithish

Hi, I’m Nithish. I’m the guy behind 21K Tools. I got tired of online tools that were slow, full of ads, paywalled or sketchy with privacy, so we built simple free ones that actually feel good to use everything runs in your browser, no account needed (maybe someday), no tracking. I write the guides here from stuff I test and use myself. Got suggestions, problems or ideas? Just email us at contact@21k.tools or fill the form at the Help Center. Follow @21ktools on X for updates.

Published Articles

Why Government Portals Reject Your Documents — Common Upload Mistakes and Exact Fixes

Why Government Portals Reject Your Documents — Common Upload Mistakes and Exact Fixes

Government portals reject documents for reasons that have nothing to do with the document itself. File too large, wrong format, wrong DPI, portrait photo on …

What is CAGR and How to Calculate It (With Real Mutual Fund Examples)

What is CAGR and How to Calculate It (With Real Mutual Fund Examples)

CAGR is the single most useful number for understanding how an investment actually performed over time. Here's the plain-language explanation, the complete formula with step-by-step …

How to Use Your Phone as a Scanner Without Any App in 2026

How to Use Your Phone as a Scanner Without Any App in 2026

You don't need CamScanner, Adobe Scan, or any third-party app to scan documents on your phone. Every iPhone and Android device already has a built-in …

CIBIL Score vs Credit Score — What's the Difference and How Is It Actually Calculated?

CIBIL Score vs Credit Score — What's the Difference and How Is It Actually Calculated?

Most Indians use CIBIL score and credit score as if they mean the same thing. They don't — but the difference is simpler than you …

Why Your Aadhaar PDF Is Password Protected — And How to Open It

Why Your Aadhaar PDF Is Password Protected — And How to Open It

Downloaded your e-Aadhaar and can't open it? The password is simpler than you think — it's your name and birth year in a specific format. …

How to Create a QR Code for Your WiFi — Step by Step

How to Create a QR Code for Your WiFi — Step by Step

Stop telling guests your WiFi password one character at a time. Creating a WiFi QR code takes under two minutes, prints beautifully, and works on …