Stax Inbox
No Jargon. Just the Truth.

Your passwords are safe.
Here's exactly why.

No technical background needed. We'll walk you through every protection we use — with plain, everyday language — so you know exactly what's keeping your data safe.

What most apps do

  • Store your passwords on their servers
  • Could read your credentials if they wanted to
  • You have to trust their promise not to look
  • One breach exposes everyone's passwords

What Stax Inbox does

  • Passwords are locked on your device before they leave
  • We only ever receive an encrypted blob we can't open
  • Technically impossible for us to read your passwords
  • Even a breach of our servers reveals nothing useful

Set up once. Locked up tight.

Here's what actually happens behind the scenes — explained like you're talking to a friend, not a textbook.

1

You choose a master password

One password to protect everything. We store only a scrambled fingerprint of it — like a photo of a cake, not the recipe. We can check "is this right?" but can never work backwards to find your password.

2

Your device builds a secret key

Your phone or computer uses your master password to build a unique secret key — entirely on your device. This key never travels to our servers. Not once. It exists only in your device's memory while the app is open.

3

Your passwords are locked before they leave

When you add a Gmail or Outlook account, its password gets locked with your secret key before it's sent anywhere. We receive a scrambled blob that's completely unreadable without your key — which we don't have.

New phone? Sign in once. Done.

Here's why a new device can unlock your accounts without us ever sending your key over the internet.

1

Sign in with your master password

On your new device, you enter your master password. That's it. No special code, no recovery key.

2

Your new device rebuilds the same key

The same password, run through the same process, always produces the same key — on any device. Your new phone rebuilds it locally, without any help from our servers.

3

Your accounts appear — fully set up

Your new device downloads the locked blobs from our server, unlocks them with the key it just rebuilt, and every email account is there, ready to go.

Bank-grade protection.
Explained simply.

We use the same encryption that governments and banks use worldwide. Here's what those terms actually mean.

What the words mean

  • 🔐

    AES-256-GCM — This is the lock. "256-bit" means there are more possible combinations than atoms in the observable universe. Your email passwords are locked with this before leaving your device.

  • 🗝️

    Argon2 / PBKDF2 — This is how your secret key is built from your master password. It's intentionally slow and heavy — making it practically impossible for someone to guess millions of passwords quickly.

  • 🫙

    bcrypt — This is how we store a fingerprint of your master password for login. It's a one-way scramble. We can check "does this match?" but can never reverse it to find the original.

  • 🚫

    Zero-knowledge — This means we genuinely cannot see your passwords. Not because of a policy — because we mathematically never receive the key needed to unlock them.

What's protecting your data
Email password lockAES-256-GCM
Secret key builderArgon2 / PBKDF2
Login check (server)bcrypt
Key length256-bit
Your key sent to usNever
Your emails through our serverNever
What we store per email account
Item Protected?
Email addressPlain text
Display namePlain text
Server addresses & portsPlain text
IMAP usernamePlain text
IMAP passwordAES-256-GCM
SMTP passwordAES-256-GCM
OAuth token (Gmail / Outlook)AES-256-GCM

What we actually receive.
And why it tells us nothing.

When your password leaves your device, it has already been transformed into something completely unreadable. Here's what that looks like — and why even the world's most powerful computers can't undo it.

Why the blob is unbreakable

  • 🔀

    Your password becomes random noise. AES-256-GCM doesn't just scramble your password — it transforms it into data that is statistically indistinguishable from random. There is no pattern. No fingerprint. Nothing to analyse.

  • 🧂

    Every blob is unique, even for the same password. We add a random "nonce" (a one-time random number) to every encryption operation. Encrypt the same password twice and you get two completely different blobs. An attacker can't even tell if two accounts share the same password.

  • The blob includes a tamper seal. The "GCM" part of AES-256-GCM adds an authentication tag — a built-in seal that proves the blob hasn't been altered since it was created. If anyone tampers with the stored blob, decryption fails immediately.

  • 🌌

    Brute force is not an option. A 256-bit key has 2256 possible combinations — a number so large that no computer ever built, or ever likely to be built, could crack it by guessing. This isn't marketing — it's mathematics.

  • 🏦

    This is what banks and governments use. AES-256 is the encryption standard mandated by the US National Security Agency for top-secret information. When your bank says your data is encrypted, this is what they mean.

What your Gmail password looks like to us

Before encryption — what you type:

MyDog$Name1sRex!

After AES-256-GCM encryption — what we receive:

// nonce (random, unique per encryption)
a3f8c21d9e047b56
3c8a1f2e5d907b4c

// encrypted payload (your password, scrambled)
7f4a2b9c1d8e3f05
6a1c4d8b2e9f307a
c5d3e1f8a2b4c906
1e8f3a5b7c2d4e09

// auth tag (tamper-proof seal)
9b2e4f1a8c3d507e
Can we read this?No
Can we guess the original?No
Can anyone tamper with it?Auth tag would fail
Is every blob unique?Yes — random nonce
Why we chose AES-256-GCM specifically
ConfidentialityAES-256 (unbreakable)
Integrity checkGCM auth tag
Unique per operationRandom nonce
Industry standardNSA, NIST approved
Used byBanks, govts, TLS/HTTPS

How your master password
becomes an unguessable key.

Your master password is just words. What actually locks your data is a completely different thing — a key that gets built from it. Here's exactly how that works, and why it makes your data safe even if someone guesses your password wrong a million times.

Why this protects you

  • 🐢

    It's deliberately slow. Argon2 and PBKDF2 are designed to take noticeable time and memory to run — even on a fast computer. This isn't a flaw. It means an attacker trying to guess your password can only try a handful per second, not billions.

  • 🧂

    A random "salt" is mixed in. Before deriving your key, we add a unique random value called a salt. This means two people with the exact same master password will produce completely different keys. Pre-computed attack lists are useless.

  • 🔁

    It runs thousands of rounds. The process doesn't run once — it loops thousands of times, feeding the output back in as the next input. Each round adds more work for any attacker, while being barely noticeable to you.

  • 📌

    Same password always makes the same key. Despite all the complexity, the result is deterministic — your password plus your salt will always produce the exact same 256-bit key, on any device, every time. That's how your new phone can unlock your accounts without us sending it anything.

  • 🏆

    Argon2 won the Password Hashing Competition. It was selected in 2015 by an international panel of cryptographers as the gold standard for exactly this job. PBKDF2 is the long-trusted standard used by Apple's own iCloud Keychain. We use both.

What key derivation looks like

Your inputs:

// your master password
password = "MyDog$Name1sRex!"

// unique random salt (stored with your account)
salt = e3a1f8c24d907b56...

// work factors (how hard to compute)
iterations = 100,000
memory = 64 MB

After Argon2 runs 100,000 rounds:

// your 256-bit secret key (never leaves your device)
3f8a1c2e9d047b56
7a4b2c8f1e306d9a
c1d5e3f7a2b8c904
9e2f4a1b8c3d507f
Guesses per second (attacker)~3
Guesses per second (normal hash)~1,000,000,000
Pre-computed lists work?No — unique salt
Same password = same key?Yes — deterministic
Why we chose Argon2 + PBKDF2
Argon22015 Password Hashing Competition winner
PBKDF2Used by Apple iCloud Keychain
Memory-hardResists GPU / hardware attacks
Tunable costGets harder as hardware improves

What we can — and can't — see.

No small print. No surprises. Here's everything, honestly.

✉️

Your Stax account email

Yes, we can see this. We need it to send you a password reset code and for account support.

🔑

Your master password

No. We only store a one-way fingerprint. We can verify it's correct but can never reverse it to find the actual password.

📬

Your email addresses

Yes — the addresses themselves, like you@gmail.com. These aren't sensitive; it's your public email identity.

⚙️

Server settings

Yes — the server addresses and port numbers. These are public technical settings, like a mailing address for a building.

🔒

Your email passwords

No. These are locked with your key before they reach us. We hold the safe — you kept the combination.

📩

Your actual emails

No. Emails travel directly between your device and Gmail, Outlook, etc. We are never in the middle of that connection.

What if you forget your master password?

We're being upfront about this because it's the one trade-off of our security model. We think it's worth it — but you should know.

We cannot recover your passwords for you.

Because we don't hold your key, we literally cannot open your locked containers. No back door. No override. This protects you — but it means forgetting your master password requires a reset.

  • 1

    You verify your identity via a code sent to your Stax Inbox account email.

  • 2

    The locked blobs are deleted. They're useless without the old key anyway. We clear them out.

  • 3

    Your non-sensitive settings are kept — server addresses, ports, usernames. Only the actual passwords are lost.

  • 4

    You re-enter each email password once. Fresh encryption begins with your new master password. Everything syncs again.

Our advice

Treat your master password like your ATM PIN. Write it down somewhere private at home — a notebook, a card in your wallet, a note in a drawer.

Not on a sticky note on your screen — but somewhere only you would think to look.

Why this is actually good news
A hacker gets our server dataGets nothing
A court orders us to hand over your passwordsWe have nothing
An employee at Stax Inbox goes rogueStill nothing
You forget your master passwordReset + re-enter once

Sound good? Get early access.

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