☺Your deviceONLY ON YOUR DEVICE↗
Hello! 👋
🔒 24 words stay hereMESSAGING WITHOUT YOUR PHONE NUMBER.
Your keys.
Your conversations.
Chat with friends, hear their voices, share your moments. The key to your Serbest account is a secret only you know: 24 private words.
No phone number. No email. No waiting for SMS.
Early access • Available on the web ↗Don’t just watch. Tap. ↙
Interactive illustration · No real account or message is created.
☺A friendhere, waiting for you
I’m here 👋✓
glad you made it. ✓✓
It starts with a tap.
A NEW ACCOUNT. A FAMILIAR HELLO.
Three steps.
Then say hello.
No technical details to memorize.
Just a key that belongs to you.
✳ ONLY ON YOUR DEVICE
Try the beginning yourself.
Tap a step. See how your device, your words and your account come together.
The app generates 24 random words on your device. This secret word sequence is the key to signing in to your account.
Interactive illustration · No real account or message is created.
Your username helps people find you. Your 24 words unlock your account.
24 WORDS = YOUR ACCOUNT’S SECRET KEY
Your words stay yours.
Really yours.
The app processes your 24 words on your device and never sends them to the server. The private keys derived from those words stay on your device too.
From one secret to two keys.
Two people, two devices. Let’s see which key stays where.
24words.
A private starting point.
A private starting point.
Private keys stay put.
Encrypted messages travel.
You
YOUR DEVICE
24secret wordsNever sent to the server.
🔒Private keyStays on the device.
↗Public keySafe to share.
Your private key + their public key✳ The same shared secret
Your public key →← Their public key⇄
☁Serbest serverDoes not receive your words.▧ 7a·9f·2c
We carry messages,while you keep the keys.
Your friend
THEIR DEVICE
24secret wordsNever sent to the server.
🔒Private keyStays on the device.
↗Public keySafe to share.
Their private key + your public key✳ The same shared secret
Your words are processed on your device.
Your private keys are derived from your 24 words on your device. Your public key can be shared. Your words and private keys are not sent to the server.
SIMPLIFIED ILLUSTRATION · Contains no real keys.Private one-to-one message flow.
NEW PHONE. SAME YOU.
Change your phone. Keep your conversations.
You bring your words to the new device. Your keys are recreated there, and your stored encrypted history opens on that device.
OLD PHONE
☺
Drag the paper onto the new phone. Or just tap it. ↗
ENCRYPTED HISTORY ON THE SERVER
▧ 7a·9f·2cNEW PHONE
LOCKED
▧ 7a·9f·2cHello! 👋 ✓✓
▧ 7a·9f·2cCoffee together? ☕ ✓✓
▧ 7a·9f·2cThat was amazing! 🎉 ✓✓
Your words are not a backup of your messages. They cannot recover messages that have been deleted or are no longer on the server.
Interactive illustration · No real account or message is created.
We don’t have a copy.
Write your 24 words on paper in the correct order and keep them somewhere safe. If you lose them and can no longer access your account, we cannot reopen it through SMS or support.
Anyone who knows your words can sign in. Never share them or reuse words from another account or wallet.
SO WHY 24 WORDS?
Bring your history.
Keep your keys.
Seeing your old messages on a new phone is convenient. The real question is: which key opens them?
Sign in to your account.
Your history comes from the cloud.
In some messaging apps, you enter a code on a new device and your old chats appear. The code arrives by SMS or in an existing session; the messages come from the service’s server, not from the SMS.
An SMS is not a backup of your messages. Using a login code does not mean your messages can only be opened with a key that belongs to you. Signing in and encrypting messages are different things.
Some apps also offer end-to-end encrypted device-bound chats. Their history may not transfer to a new device through the cloud. Each app handles this differently.
Enter your words.
Your device recreates your keys.
Use the same 24 words on your new device. It recreates the same private keys and opens the encrypted history received from the server locally.
You don’t download your private keys. The server stores encrypted message data, not your words.
This is your Serbest account’s history. It does not import messages from other apps or recreate deleted data.
Where exactly do my words stay? ↑IT STARTS WITH A MESSAGE. SEE WHERE IT GOES.
Familiar conversations.
A fresh start with Serbest.
Voice, video, stickers. Better together.
Tap a feature for a closer look. ↙
Screens from Serbest and features we’re developing. Availability varies by device and chat type. What’s in early access? ↗
Group chats
Better with everyone here.
Bring your friends into one conversation. Plans, ideas and all those inside jokes, together.
Mobile web · Our Crew group chat · Captured with fictional demo accounts.
YOUR TURN. JOIN THE GAME.
Take a guess,
orangutan.
Choose the dictionary. Grow the vault. How many guesses will the orangutan need?
Changing the dictionary or length creates a new vault. Words may repeat; their order matters.
4-word dictionary · 1-word sequence
This vault’s dictionary: banana, cloud, skate, lemon.
44possibilities
Chance in one guess: 1 / 4
JavaScript is required to play. The explanation below is always available.
This is a toy vault. We never ask for your real sign-in words. Your choices and attempts stay on this page.
THE ORANGUTAN’S TURN.
Let’s see it try.
It can start before you guess. Each time you continue, it tries new sequences.
Last sequence tried
Waiting for the first attempt.
- Tried / all possibilities
- 0 / 4
- Time spent trying
- 0 seconds
- Speed measured in this game
- Not measured yet
Show recent attempts
Every candidate is actually compared. Fast mode shows the last six sequences; the counter includes them all. Time includes visual delays but excludes time spent paused.
WHAT ABOUT A 2,048-WORD DICTIONARY AND A 24-WORD SEQUENCE?
From a toy vault to the real scale.
A securely generated 24-word phrase with a valid BIP39 checksum has 2256 different phrases to choose from.
0%If the same number of candidates were tried at the real scale, this is the fraction that would have been covered.
This shows the share of all possibilities you have checked, not how close you are to the right words.
Average time to find it at the measured game speedLet the orangutan try first.Assumes the game speed, including visual pauses, stays the same.
Average time to find it · the selected speed is an assumption.
How are these numbers calculated?
Coverage = different attempts ÷ 2256 × 100. For equally likely sequences, the average search time without repetition = (possibilities + 1) ÷ 2 ÷ attempts per second. A full search takes about twice as long.
Choosing each position freely from 2,048 words gives a raw total of 2,04824 = 2264 sequences. BIP39’s 8 checksum bits limit valid phrases to 2256 . This comparison uses that set of valid phrases.
The game only compares word sequences. It does not measure actual key derivation or decryption speed. Times are hypothetical calculations at a constant speed; real hardware and protocols differ. Words you choose yourself cannot be assumed to have the same resistance to guessing.
Source of the calculation · BIP39 ↗The orangutan has a tough job here. 🦧One guess, one centimeter.
One guess, one centimeter.
Even the universe isn’t enough.
Leave the toy dictionary behind. Imagine a secret sequence of 24 words from a dictionary of 2,048 words. To open the vault, you need every word in the right order.
Make one guess.
For each different word sequence you try, draw a line one centimeter long on the ground.
Extend it with every attempt.
Another guess, another line. How long would the path need to be to try every possibility?
Cross the universe. Still not enough.
Even if you reached from one end of the observable universe to the other, you would have tried only a tiny fraction of the possibilities along the way.
An analogy to help imagine the scale. Illustrations are not to scale.
Curious? Calculations and sources ↗
A securely generated random 24-word BIP39 phrase represents 2256 different starting values. Assigning one centimeter to each gives a path of roughly 1.2 × 1059 light-years in length. The observable universe is about 92 billion light-years across.
Calculation: 2256 cm ÷ (9.46 × 1017 cm/light-year). This is a distance analogy for the number of possibilities, not a measurement of attack time. The observable universe is not the whole universe.
In BIP39, 24 words encode 256 bits of randomness and 8 checksum bits. The calculation is therefore not simply 2,048 to the power of 24. The number of starting values alone does not guarantee the security of the whole app.
By “impossible,” we mean that guessing every possibility is not practical. This strength depends on your device generating the words securely at random. Picking 24 words yourself does not provide the same strength. Keep your words private and safe.
HOW DOES SECURITY WORK?
We carry the message.
You keep the secret.
Private one-to-one texts are encrypted on your device before they are sent. They are opened on the recipient’s device. This is called end-to-end encryption.
IDENTITY STARTS ON YOUR DEVICE
From 24 words to your identity.
Your device derives your private keys from your words. Instead of your words or private keys, the server receives public identity information and protocol data that verifies your sign-in.
Private content and traffic information are different: the server can see who communicates with whom, when, and the amount of data. Open groups and channels contain public content.
What are the limits of early access?
Private one-to-one text and encrypted file flows on Android have been verified locally. Web uploads, private groups and full feature parity across devices are not complete. Feature screenshots do not mean that every flow has been included in this security scope.
Anyone who obtains your words can open encrypted history they can access. Device security matters. Independent security review and a separate security-code check of the other person’s key are not complete. We make no claim of post-quantum protection.
LET’S CLEAR THINGS UP.
Good questions.
Straight answers.
Do I need to memorize all 24 words?
No. Write the words down in the correct order and keep them somewhere safe. Use your signed-in session for everyday chats; you don’t enter the words for every message. You need them when signing in again or using a new device.
If the words stay on my device, how do I sign in on a new phone?
You don’t download your words from the server. You enter them on the new device from your own backup. On the same Serbest service, the same words recreate the same keys. Your encrypted history is downloaded and opened on your device. Your old phone doesn’t need to be online. Deleted messages cannot be brought back.
Can you recover my account if I lose my words?
We don’t have a copy of your words or a recovery key that unlocks your account. If you lose your words and can no longer access your account, we cannot reset it by SMS, email or through support. That’s why keeping an offline backup when you sign up matters.
What does my friend need to chat with me?
Just a Serbest account of their own. Find each other by username. You don’t share your phone number or your 24 words. Anyone who knows your words can sign in to your account, so never share them, even with a friend or someone claiming to be support.
Will my account or old messages from another app appear here?
You create a new account on Serbest. You don’t sign in with an account from another messaging service, and messages from other apps are not imported automatically. Here, “history” means messages created in your Serbest account that are still stored. These 24 words are not a crypto wallet either; don’t reuse words from another service.
What can I try today?
Serbest is in early access. The web and Android links on this page currently open our local development environment, so you need to be on the same network. Private one-to-one text messaging, signing in on a new device with the same words, and opening history have been verified locally. Encrypted files on Android have also been verified. Web uploads, private groups, feature parity across devices and independent security review are still in progress.
BRING A FRIEND, NOT YOUR PHONE NUMBER.
The first hello
is yours to send.
Try it on the webAndroid APK coming soon
Early access • New accounts require an invitation.
What works today? ↗