About ToolSec

ToolSec is a free collection of 29 online tools for security engineers, network administrators, developers, DevOps teams and IT managers. From calculating subnets and generating hashes to decoding JWTs, formatting JSON and estimating security risk, our goal is to provide fast, accurate, privacy-respecting utilities for the work technical professionals do every day.

Our mission

Too many online utilities are slow, buried in ads, or — worst of all — quietly send the data you paste in to a remote server. We set out to build the opposite: a focused toolkit that loads instantly, respects your privacy completely, and teaches the concepts behind each tool instead of treating you like you should already know them.

What you'll find here

Our 29 tools are organized into 5 categories:

• Network & IP — Subnet, CIDR, IPv4/IPv6 and other network calculations for infrastructure engineers and sysadmins.
• Crypto & Encoding — Hash, Base64, JWT, HMAC, URL encode/decode — an encoding & decoding toolkit for developers.
• Passwords & Secrets — Generate strong passwords, measure entropy, create API keys and manage password policies.
• Compliance & Risk — Estimate risk costs, GDPR fines and security ROI — calculators for managers and CISOs.
• DevOps Utilities — Cron, JSON, YAML, regex, redirects — everyday utilities for DevOps and backend engineers.

How our tools work

Every tool on ToolSec runs entirely in your browser using JavaScript and the standard Web Crypto API. When you hash text, generate a key or decode a token, the computation happens on your own device. The data you enter — IP addresses, passwords, API keys, tokens, payloads — is never transmitted to or stored on our servers. You can verify this yourself: open the Network tab in your browser's developer tools and you'll see no request carrying your input.

Accuracy & editorial standards

We take correctness seriously. The logic behind each calculator and converter is covered by an automated test suite that validates output against published reference values — standard cryptographic test vectors, documented cron semantics, RFC-defined formats and well-known algorithms. Every tool page also explains its method and assumptions so you can check the reasoning, not just the result.

That said, our tools are provided for information and convenience. Estimators such as the breach-cost and GDPR calculators are illustrative and are not legal, financial or professional advice. Always verify important results — and consult a qualified professional for compliance decisions — before relying on them.

Who's behind ToolSec

ToolSec is founded and edited by Justin Le, who builds the tools and writes the guides and research, with backgrounds spanning software development, networking and information security. The tools here are the ones we wanted to exist ourselves — built, used in our own work, and refined based on feedback from the community. Found a bug or have an idea? We'd genuinely like to hear it — reach us via the contact page or connect on LinkedIn.

What ToolSec is not

• It is not a data-collection service — we don't ingest, log or sell the values you enter into tools.
• It is not a replacement for professional advice on legal, compliance or high-stakes security decisions.
• It is not a place to store secrets — tools generate and process data in the moment; nothing is saved.

How we keep it free

ToolSec is supported by display advertising and a small number of relevant product referrals. This lets us keep every tool free, with no account or subscription required. We label referral links and never let advertising compromise the privacy-first way the tools work. For details on cookies and ads, see our Privacy Policy.