Security tools

Everywhere else on this site, running locally is a strong preference. Here it is the whole point: a password, a token or a secret sent to a server to be processed has already been disclosed.

Nothing you type is transmitted

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termiva pass --length 20

Password Generator

Strong passwords and passphrases

open termiva pass --check

Password Strength Checker

How long it would take to crack

open termiva hash --sha256

Hash Generator

SHA-256, SHA-512, MD5

open termiva uuid --count 10

UUID Generator

Version 4 identifiers in bulk

open termiva base64 --encode

Base64 Encoder and Decoder

Encode and decode, both ways

open termiva jwt --decode

JWT Decoder

Read a token without sending it

open termiva encrypt --aes256

Encrypt Text

AES-256 with a passphrase

open termiva url --encode

URL Encoder and Decoder

Percent-encoding, done correctly

open termiva verify --sha256

Checksum Verifier

Confirm a download is intact

open termiva qr --encode

QR Code Generator

PNG or SVG, no tracking redirect

open termiva qr --decode

QR Code Reader

See where a code leads first

open termiva random --range 1-100

Why this section could not work any other way

A password strength checker that uploads what you type has been given your password. A JWT decoder that uploads a token has been handed a live credential. A password generator running on someone else's server produced a password that server has seen.

None of that is hypothetical. It is how these tools are normally built. And once your password has left your machine, you have no way to find out what happened to it.

Everything here uses your browser's own Web Crypto API, the same code that protects HTTPS. Watch the Network tab while you type and you will see nothing. Or disconnect from the internet: the tools carry on working, because there was never anything to send.

Which tool do you need?

Passwords

The generator produces random strings or memorable passphrases from the cryptographic random source, with unbiased selection. The strength checker estimates entropy and offline crack time, and flags the patterns the arithmetic cannot see.

Integrity

Hashing fingerprints text or a file with SHA-256 and four other algorithms — including MD5 and SHA-1, which are broken and included only for verifying legacy checksums. UUIDs generates identifiers that need no coordination to stay unique. The checksum verifier takes the digest a publisher listed and tells you whether your download matches it — hashing a multi-gigabyte ISO locally rather than uploading it to be checked, which would defeat the purpose entirely.

Encoding and tokens

Base64 encodes and decodes with proper Unicode support, which most tools get wrong. The JWT decoder reads a token's claims and expiry without transmitting the credential. The URL tool handles percent-encoding both ways and takes an address apart, naming the parameters that identify you rather than the page.

QR codes

The generator puts your content directly into the code, with no redirect through anyone's server — so it cannot be counted, switched off, or put behind a subscription later. The reader does the opposite job: it shows you where a code leads before you follow it, and names the tricks used to disguise a destination.

Secrecy and chance

Encryption protects a message with AES-256-GCM and a passphrase — for sending a secret through a channel you do not trust. The random number generator draws numbers, dice and prize winners from the same cryptographic source, with the modulo bias that skews most simple generators removed.