ABOUT SFRANKEY

SFranKey · Security & Developer Tools

Useful tools. Your data stays yours.

SFranKey is a focused toolbox for security and development. On-device utilities keep sensitive values in the browser, while network diagnostics disclose exactly when a connection is required.

Explore tools (23)Read our privacy model

✓ 23 tools✓ 6 categories✓ VI · EN✓ 13 on-device · 10 network-required

sfrankey://security-audit

Zero-Telemetry Verified

Isolated In-Memory Sandbox[RAM_SANDBOX]

ACTIVE

All data cycles execute in volatile RAM, auto-flushed on tab close

Telemetry & Tracker Audit[ZERO_TELEMETRY]

VERIFIED

WebCrypto Cryptographic Engine[CSPRNG_ENGINE]

READY

Strict Network Boundary[NETWORK_BOUNDARY]

SECURED

Zero sensitive data uploadsTLS 1.3 / CSP Level 3

WHY SFRANKEY EXISTS

Small utilities should not require big privacy tradeoffs.

Everyday security and developer tasks are useful enough to deserve a clear, calm and trustworthy place to run.

Scattered utilities

A small task should not mean opening a different website for every format, code or checksum.

Unclear privacy

People deserve to know where an input goes before they paste a secret, token, password or file.

Unnecessary friction

Simple tasks should not require an account, distracting ads or an interface built around upsells.

SFranKey brings the everyday essentials into one focused workspace: useful, fast and transparent by design.

THE PRODUCT MANIFESTO

Designed to help you finish a task, then leave.

SFranKey is not trying to become a place that stores your data. It is designed to help you complete a task and move on, while sensitive values remain under your control.

SFranKey · Security & Developer Tools

RAM ONLY

Local-first

Sensitive tool input is processed in browser memory whenever the job can be completed there.

NO TELEMETRY

Transparent by default

Each tool explains what it uses, what it returns and where its real limits are.

ZERO ACCOUNT

Less friction

No account, vault or onboarding is required to use the toolbox.

HONEST CODE

Right expectations

Decode is not verify, hashing is not encryption and crack time is only an estimate.

HOW SFRANKEY WORKS

The shortest useful path from input to result.

Most tools follow a simple local path. The browser receives the input, runs the tool logic and returns a result without uploading the sensitive value.

✓ No upload✓ No secret API request

SFRANKEY

Local path

No upload

User input

A secret, password, token, image, file or developer value.

Browser memory

Tool logic runs locally while the page is open.

Local result

Copy, inspect, download or reset when you are done.

Optional network path

An explicit boundary for network diagnostics

On-device tools keep sensitive input in browser memory. Network diagnostics only connect after you choose an action and disclose the destination before the request starts.

Time sync returns only a timestamp

Network checks disclose the API, provider or target involved

THE TOOLBOX

A small ecosystem for everyday work.

The toolbox spans local utilities and explicit network diagnostics in Vietnamese and English. This map is generated from the same registry used by navigation, search and the catalog.

tools

2FA & OTP

2 tools

Two-factor authentication & real-time time-based OTP codes

Passwords

2 tools

CSPRNG random password generator & offline entropy audit

QR Code

2 tools

Vector QR generator & camera scanner with SVG/PNG exports

Encoding & Hashing

3 tools

Base64 codecs, SHA/MD5 cryptographic hashes & file digests

Developer

4 tools

JSON formatter, JWT decoder, UUID generator & developer suite

Network intelligence

10 tools

IP diagnostics, network ping, DNS lookup & connectivity checks

UNDER THE INTERFACE

A little technology, used with restraint.

The implementation details matter because they support the promise: sensitive work stays close to the person using the tool.

Web Crypto

Passwords and UUIDs use the browser's cryptographically secure random source.

Offline analysis

The strength analyzer and passphrase wordlist run locally; passwords are not sent for lookup.

Browser memory

Sensitive values do not enter URLs, preferences, cookies or analytics events.

Explicit API boundary

The API serves health, time sync, feedback and opt-in network diagnostics with a visible data boundary.

CLEAR LIMITS

Privacy is also about honest expectations.

A local tool can still be the wrong tool for a job. We make those boundaries visible so the result is easier to trust.

JWT Decoder only decodes

It does not verify a token signature or prove that a token is trustworthy.

Encoding is not encryption

Base64 changes representation and hashing creates a digest; neither hides data like encryption does.

Crack time is an estimate

Password strength timing depends on hardware, rate limits, algorithms and attacker models.

Check QR links first

A QR reader shows content before opening a link so you can decide what to trust.

Not a security replacement

SFranKey complements, but does not replace, a password manager, audit or security professional.

READY WHEN YOU ARE

Use useful tools without handing your data to a black box.

Start with a local-first tool, see how it behaves and keep control of the values you bring into the workspace.

Explore tools (23)Request a tool

Architecture specs:Read privacy model Read security baseline

100% On-Device & Private

Zero sensitive data uploads

No Registration Required

Instant access directly in your browser