Free privacy tool

How long would your PIN survive?

The same PIN can fall in seconds or outlive the universe. What matters is what stands between a guess and an answer. Pick a shape (never your real PIN) and see how the same secret holds up against three very different attacks.

We never ask for your PIN, only its shape

Pick a secret to test

Combinations to try:

What the “25th word” is, and why Sealby has none

This preset is about crypto wallets, not Sealby. Some wallets let you add an optional extra passphrase on top of a 12-word or 24-word seed phrase. BIP39 calls it a passphrase. Most people call it the “25th word”. Sealby has no such option, and its own 12-word recovery phrase has a separate button above. That extra passphrase is what this preset measures. Set one, and a thief who copies the seed alone just opens an empty wallet. The passphrase you chose is then the entire barrier, and the combinations above are exactly its size. Pick the shape of that passphrase in the controls above.

The flip side is unforgiving. With no passphrase, or a blank one, there is nothing here to brute-force. The seed IS the wallet, and the moment it is copied the funds are already gone. No row below applies.

BIP39 stretches the passphrase into a seed with PBKDF2-HMAC-SHA512 at 2,048 iterations. That is fast, and not memory-hard. So the honest attack is the offline “weak protection” lane. Each guess pays those 2,048 iterations plus an address derivation to test it, so set that lane’s rate to your assumed rig speed ÷ ~2,048. The Argon2id lane is shown only as a contrast, to show what a memory-hard secret would cost. It is NOT what BIP39 does.

The on-phone lane is hidden here: a stolen seed is ground offline, with no device rate-limiter in the loop.

Practice and protect the real thing

BIP39 practice studio: rehearse the seed & passphrase →Where do you keep your seed phrase? A 60-second check →Clipboard hijack demo: how a stolen address happens →

How Sealby’s 12-word recovery phrase holds up

Every Sealby vault has its own recovery phrase. It is 12 words from the standard BIP39 English list of 2,048 words. Sealby creates it when you first save into a new vault. There is no master phrase that opens every vault. That phrase, not your PIN, is the true key to that vault. Whoever has the words can open it. The phrase is also what restores a vault from the encrypted iCloud backup onto a fresh install.

Twelve words sound short. They are not. The last word carries a 4-bit checksum, so 2^128 phrases are valid. That is a 39-digit number, and it is the figure shown above. An attacker needs your encrypted data first, from a backup or from the phone. Guessing then runs offline, with no device limit in the way. Each guess still costs the BIP39 stretch, PBKDF2-HMAC-SHA512 at 2,048 rounds, plus a key derivation and a decryption attempt. At this size that cost barely matters. Even a billion guesses a second would run for hundreds of billions of times the age of the universe.

Sealby has no “25th word”. There is no optional extra passphrase to add, and the 12 words are the whole key. Your PIN and your phrase protect different things. The PIN is short, so it leans on the phone’s attempt limits and on Argon2id. The phrase leans on its size alone, and that is enough. Whoever has the 12 words can open that vault without the PIN.

So the real risk is never brute force. It is the paper. Keep the words on paper, off the phone, and stored away from it. Never screenshot them. Never type a real recovery phrase into any website, including this one. This tool only asks for the shape of a secret, never a phrase or a PIN.

There is no reset, ever. Nobody at Sealby can recover a vault whose phrase and device are both gone. Lose the phone and the phrase, and the vault is gone with them.

The on-phone lane is hidden here: an attacker working on the phrase already holds a copy of the encrypted data, so no device limits the guessing.

Keep the real thing safe

Where do you keep your phrase? A 60-second storage check →

Three attacks, one secret

On the phone: a handful of tries, not a timeline

A real iPhone is not an unlimited guessing service. Failed attempts trigger growing delays, and after 10 failures the device must be restored, or erases itself if Erase Data is on. The honest measure here is odds, not time.

Per Apple’s passcode guidance: growing delays after failed attempts. After 10 failures the iPhone must be restored, or erases itself if Erase Data is on. ↗

Offline, weak protection

The vault file leaked, and it was protected with a plain fast hash. A cracking rig tries billions of guesses per second.

Offline, Argon2idSealby protection

Same leaked file, but the key comes from a memory-hard function. Every guess costs real memory and time; GPU farms lose their edge.

Argon2id is the key-derivation function Sealby uses, and this lane is the conservative floor, not the whole story. In Sealby, vault keys are also wrapped by a key bound to your device’s Secure Enclave. An attacker holding only your Encrypted Backup data cannot grind your PIN at all. Without your unlocked device they would need your recovery phrase, and that is 128 bits.

1 min1 hour1 day1 year1,000 yuniverse

The assumptions: edit them

Every number above comes from three rates and one formula. Change the rates and watch the times follow. Nothing else is hidden in the math.

offline: median time = combinations ÷ 2 ÷ guess rate · on-phone: odds = attempts ÷ combinations

On-phone attempts before lockoutReal iPhones allow only a handful of tries: escalating delays, then a forced restore (or erase) after 10 failures. Editable for hypothetical devices.Fast-hash guesses per second (illustrative)Illustrative default. Real speed varies enormously with the hash, its parameters, and hardware.Argon2id guesses per second (illustrative)Illustrative default. Memory-hardness removes the GPU advantage, but the real rate depends on the chosen Argon2id parameters.

These times assume a randomly chosen secret. Human favorites such as 1234, birth years and password1 fall instantly in every scenario, because attackers try them first.

Same PIN, three fates

Notice what changed between the rows: never the PIN, only the machinery around it. On the phone, the game isn’t time at all. An attacker gets a handful of tries against long odds before the device locks up or erases. If the encrypted data ever leaves the device, those protections vanish. The PIN stands alone against hardware built to guess, and only the cost of each guess protects it.

That cost is what a memory-hard key derivation buys. Argon2id makes every single guess expensive in memory and time, so the rig that ate a fast hash for breakfast slows to a crawl.

Why Sealby calibrates Argon2id on your device

Sealby derives your vault key with Argon2id tuned on your actual iPhone. The parameters are measured per device, so one unlock costs a deliberate fraction of a second. You barely feel it once. A cracking rig has to pay it billions of times. Layered on the Secure Enclave’s rate limits on the device, both bars above are working for you at once.

How Sealby’s encryption works →

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Free to use and link. The quickest way to show someone why “it has a PIN” isn’t the whole story.

<a href="https://sealby.app/en-au/tools/pin-crack-time">How long would your PIN survive? Honest crack-time visualizer</a>

Your PIN deserves better machinery.

Sealby seals your photos and files with AES-256 behind Argon2id calibrated for your device. The numbers in the slow lane above are the ones that apply to you.

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iPhone & iPad · iOS 17+ · Free