Cybersecurity Tools
A short, opinionated list of free cybersecurity and privacy tools: breach and exposure checks, fingerprint and IP-leak tests, privacy DNS, VPN and proxies, plus my own browser-based tools.
Cybersecurity & privacy tools I actually use
A short, opinionated list of free tools for checking what is exposed about you, hardening your connection, and testing your own setup. Two kinds here: the interactive tools I built and run on this site, and the external services I reach for. No fluff, no affiliate padding, only things worth bookmarking.
My free, browser-based tools
These run entirely in your browser. Nothing you type leaves your device, no signup, no tracking.
Real entropy and crack-time for any password, plus a privacy-preserving check of whether it has leaked in known breaches.
An honest read of how exposed you are to data brokers, with a real, free opt-out plan.
Compute, identify, and compare cryptographic hashes, and see how avalanche behaves, all client-side.
Generate strong passwords from your browser's cryptographic randomness, with a live strength read.
See what is exposed about you
Before you can fix your footprint, you have to see it. These check what is already public, leaked, or fingerprintable.
The canonical breach lookup, run by Troy Hunt. Check whether your email or phone has appeared in known data breaches.
Shows how identifiable your browser is from its fingerprint alone, even without cookies.
Reveals the IP, DNS, and WebRTC data your browser leaks. The fastest way to confirm a VPN is actually working.
A quick reputation check on a suspicious domain before you trust it with a click or a card number.
Instant disposable inboxes for testing signups and flows without handing over your real address.
Harden your connection
Privacy-respecting DNS, VPN, and proxy tools to shrink what your network and the sites you visit can see.
Cloudflare's free, fast, privacy-respecting DNS resolver, with an optional app for phones.
Independently audited, no-logs VPN with a genuinely usable free tier, from the Proton Mail team.
Open-source encrypted proxy designed to slip past restrictive firewalls. Self-hosted, not a service.
A non-caching filtering proxy that strips ads, trackers, and junk headers before they reach your browser.
More from this site
If you are securing more than yourself, these go further than a tool list.
Every interactive tool and checklist on the site, in one place.
The single highest-leverage upgrade for most people, ranked on security, UX, and value.
Canonical standards, frameworks, and primary sources, organised for actual use.
Original analysis on identity, AI security, and the markets shaping them.
More from Deepak Gupta
Every page on guptadeepak.com is hand-curated by Deepak Gupta. Pick a thread:
- About Deepak Gupta
Founder, cybersecurity architect, and writer at guptadeepak.com.
- My journey
From LoginRadius (2013, 1B+ users) to GrackerAI, in milestones.
- Publications & patents
Books, free e-books, a journal special issue, and five granted patents.
- Research Hub
Curated research, buyer's guides, vendor comparisons, and technical deep-dives.
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