Z-TEXT is a zk-SNARKs blockchain messenger. Z-TEXT requires no phone number, no email, and no SIM. Z-TEXT collects zero metadata. Z-TEXT combines a shielded messenger, a password manager, and a crypto wallet in one app. Z-TEXT is built on the BitcoinZ blockchain since September 10, 2017.

What is the best messaging app with no phone number?

Z-TEXT is a leading messaging app with no phone number. Your identity is a cryptographic z-address on the BitcoinZ blockchain. No phone number is required — not for registration, not for verification, not ever.

How much does Z-TEXT cost?

The Z-TEXT Cyberpunk Lifetime License costs $128.52 one time. No subscription. 1 million possible messages are included and the license never expires. Payment accepted in BTCZ, ZEC, BTC, ETH, USDT and more. There is also a Zero Trace 1-month plan at $3.00.

Is Z-TEXT quantum resistant?

Yes. Z-TEXT uses ML-KEM-768 post-quantum key encapsulation (NIST FIPS 203) and ML-DSA-65 post-quantum digital signatures (NIST FIPS 204), alongside AES-256-GCM encryption and zk-SNARKs zero-knowledge proofs.

What is panic mode in Z-TEXT?

Panic mode in Z-TEXT uses a second PIN called the Panic PIN. If you enter the Panic PIN instead of your real PIN, the app wipes itself instantly. Your real data stays safe on the blockchain and is fully recoverable with your 24-word seed phrase on any clean device.

What is stealth mode in Z-TEXT?

Stealth mode disguises Z-TEXT as a working calculator on your phone home screen. You open the calculator and type a secret code as a math equation to unlock the app. To anyone inspecting your device — at a border crossing, under coercion, or during a casual check — it looks like an ordinary calculator.

What happens if I lose my phone?

Enter your 24-word seed phrase on any new device. Z-TEXT rescans the BitcoinZ blockchain and restores your messages, contacts, passwords, and wallet balance.

What does the blockchain reveal about a Z-TEXT message?

Very little. A blockchain explorer shows a transaction ID, a block height, and confirmations. No sender, no receiver, no message content, and no identity are exposed.

How does Z-TEXT compare to Signal?

Z-TEXT requires no phone number. Signal requires a phone number. Z-TEXT has no phone numbers to hand over. Z-TEXT is post-quantum protected.

zk-SNARKs stands for Zero-Knowledge Succinct Non-Interactive Arguments of Knowledge. It is a cryptographic method that proves a transaction happened without revealing who sent it, who received it, or what it contained. Z-TEXT uses zk-SNARKs to shield every message on the BitcoinZ blockchain.

Is Z-TEXT safe for journalists?

Yes. Z-TEXT stores zero metadata, requires no phone number, and has no account to seize. Panic mode wipes the app instantly if a device is taken. Stealth mode hides the app as a calculator. Journalists and their sources are protected at every layer.

How do you verify a ZKStamp proof?

The owner shares the transaction ID and the viewing key of one proof. Anyone then runs ZCheck, an open-source script, on their own BitcoinZ node with the original file. ZCheck answers VALID if the fingerprints match, and NOT VALID if even one character of the file changed.

Why use a shielded timestamp instead of a public one?

A public blockchain timestamp shows the fingerprint to everyone, so anyone holding the same file can link it to you. A shielded ZKStamp proof hides the fingerprint and the addresses. The owner reveals one proof at a time, only when needed, with its viewing key.

Can AI agents use ZKStamp Proof-100?

Yes. ZKStamp Proof-100 has an MCP endpoint at https://proof.zketernity.app/mcp with three tools: timestamp_fingerprint, timestamp_text and check_balance. An AI agent such as Claude can stamp a text or fingerprint in one sentence.

How much does ZKStamp Proof-100 cost?

One pack of 100 proofs costs 500,000 BTCZ, paid in BTCZ only. Payment is credited automatically after 2 confirmations. No card, no email and no account name are needed.

ZKStamp, Proof of Existence, BitcoinZ, zk-SNARKs, AI Agents, Blockchain Timestamp

Proof of Existence, Shielded: ZKStamp Proof-100 Is Live

ZKStamp Proof-100 writes a file's fingerprint to the BitcoinZ blockchain, shielded. You get a dated proof that only you can reveal. AI agents can use it directly.

A real ZKStamp proof: BitcoinZ block 1,862,988, 27 October 2026. Stamp it with Z. Before Q.

ZKStamp Proof-100 is live. It comes from the team behind Z-TEXT, the privacy messenger on the BitcoinZ blockchain that needs no phone number. Z-TEXT protects what you say. ZKStamp proves when you said it, or made it, without showing it to anyone.

One sentence to an AI agent. One shielded transaction. One proof you can reveal on your terms.

In short

ZKStamp Proof-100 writes the SHA-256 fingerprint of a file or text to the BitcoinZ blockchain, inside a shielded zk-SNARK transaction. The block dates it. Nobody can see the fingerprint or who made it, until the owner reveals one proof with its viewing key. Anyone can then check it with ZCheck, an open-source script, on their own node. AI agents use it through MCP. A pack of 100 proofs costs 500,000 BTCZ.

❓ 1. What is ZKStamp Proof-100?

ZKStamp Proof-100 is a proof of existence service. Proof of existence means a dated record showing that a piece of data existed at a given time, without revealing the data itself.

ZKStamp never sees your file. It only receives its SHA-256 fingerprint: a 64-character code computed from the file. Change one comma and the fingerprint changes completely. SHA-256 belongs to the SHA-2 family, designed by the US National Security Agency and published in 2001. (Source: Wikipedia, SHA-2)

ZKStamp writes that fingerprint into the encrypted memo of a shielded BitcoinZ transaction. Shielded means zk-SNARKs zero-knowledge proofs hide the sender, the receiver, the amount and the memo on the blockchain. (Source: BitcoinZ)

Three names, one system:

ZKStamp is the brand.
Proof-100 is what you buy: a pack of 100 proofs.
ZCheck is how anyone checks a proof.

Mini-resume

ZKStamp Proof-100 is a proof of existence service on the BitcoinZ blockchain. It writes only the SHA-256 fingerprint of a file or text, never the file, into a shielded zk-SNARK transaction. The block's timestamp dates the proof. ZKStamp is the brand, Proof-100 is the 100-proof pack, and ZCheck is the verification tool.

❓ 2. What does the demo show?

The video below is a real run, on 27 October 2026. No staging, no mockup.

We asked Claude, an AI agent: "Use Proof-100 to timestamp this text: My secret invention idea: a lock that opens with a song."
Claude called the Proof-100 tool. The fingerprint went on-chain in block 1,862,988, at 09:33 UTC. (Source: BitcoinZ explorer)
On the public explorer, the transaction exists. But it shows no inputs, no outputs, nothing inside.
ZCheck, run on a separate node with the viewing key and the exact sentence: VALID.
Same check, "song" changed to "sing": NOT VALID.

One letter. That's all it takes to break the proof.

Mini-resume

In a real ZKStamp demo on 27 October 2026, Claude stamped an invention idea through Proof-100 in one sentence. The proof landed in BitcoinZ block 1,862,988 at 09:33 UTC. The public explorer showed the transaction but nothing inside it. ZCheck answered VALID with the exact sentence, and NOT VALID after changing one letter.

❓ 3. How does a ZKStamp proof work, step by step?

1. Fingerprint

Your machine (or your AI agent) computes the SHA-256 fingerprint. The file never leaves your machine.

2. Stamp

ZKStamp sends a shielded transaction to a brand-new address made for this one proof. The fingerprint sits in its encrypted memo. It takes about 10 to 60 seconds.

3. Receipt

You get the transaction ID and that address's viewing key. Keep the viewing key. Without it, that proof can't be revealed.

4. Reveal, when you choose

Share the transaction ID and viewing key of one proof. That reveals this one proof and nothing else: not your other proofs, not your account.

5. Check, without trusting us

Anyone runs ZCheck on their own BitcoinZ node. ZCheck reads the fingerprint straight from the blockchain and compares it with the file. VALID or NOT VALID, with the block and the date.

Mini-resume

A ZKStamp proof works in five steps. The user's machine computes the SHA-256 fingerprint. ZKStamp writes it into a shielded BitcoinZ transaction sent to a new address. The user receives the transaction ID and a viewing key. The user reveals one proof by sharing both. Anyone verifies it with ZCheck on their own BitcoinZ node, without trusting ZKStamp.

❓ 4. Why shielded, when blockchain timestamps already exist?

Blockchain timestamping isn't new, and we won't pretend it is. Researchers described writing file hashes into the Bitcoin blockchain back in 2015, with the OriginStamp service. (Sources: Gipp, Meuschke and Gernandt, 2015, Wikipedia, Trusted timestamping)

But on a public chain, the fingerprint is public too. Anyone holding the same file can compute it, search the chain and find your stamp. Your rivals included.

ZKStamp flips that. The fingerprint hides inside a shielded memo. Your proofs sit there, dated and silent, until you decide which one to show, and to whom.

Public timestamp

Fingerprint visible to everyone, forever
Your stamps can be linked together

ZKStamp (shielded)

Fingerprint hidden in an encrypted memo
One new address per proof; reveal one at a time

Mini-resume

Blockchain timestamping has existed since at least 2015, but on public chains the fingerprint is visible to everyone and stamps can be linked. ZKStamp writes the fingerprint into a shielded BitcoinZ memo, one new address per proof. The owner reveals each proof separately, only when needed.

❓ 5. Who is ZKStamp Proof-100 for?

Developers and AI agents first. ZKStamp speaks MCP (Model Context Protocol), the standard way for AI assistants to use outside tools. Plug the MCP address into Claude with your key, and your agent can stamp in one sentence.

MCP: https://proof.zketernity.app/mcp
Tools: timestamp_fingerprint, timestamp_text, check_balance
REST API for scripts and servers
Guide for AI agents: proof.zketernity.app/llms.txt

What to stamp? An invention idea before you pitch it. A manuscript before you send it out. Code before a release. A dataset, or an AI output, the day it was made. In my view, anyone who creates and shares will want this kind of receipt sooner or later.

Mini-resume

ZKStamp Proof-100 targets developers and AI agents. It offers an MCP endpoint at proof.zketernity.app/mcp with three tools (timestamp_fingerprint, timestamp_text, check_balance), a REST API, and an llms.txt guide. Typical uses: invention ideas, manuscripts, code releases, datasets and AI outputs.

❓ 6. How much does it cost, and how do I pay?

500,000 BTCZ for 100 proofs. Paid in BTCZ only. No card, no email, no account name.

Create an account: you get a key and your own deposit address.
Send 500,000 BTCZ to that address.
After 2 confirmations, about 5 minutes, 100 proofs are credited automatically.

No BTCZ yet? Write to contact@z-text.com. We'll help you find where to get BTCZ.

Mini-resume

A ZKStamp Proof-100 pack costs 500,000 BTCZ for 100 proofs, paid only in BTCZ, with no card, email or account name. The buyer creates an account, pays to a personal deposit address, and receives 100 proofs automatically after 2 confirmations.

❓ 7. "Stamp it with Z. Before Q." What does Q mean?

Q is the day quantum computers get strong enough to break some of today's cryptography. Nobody knows when.

Here's the honest split. The date of your proof rests on SHA-256 and the blockchain record, which are expected to hold up well against quantum computers. The privacy of the shielded transaction rests on today's zk-SNARK cryptography, which is not post-quantum. A future quantum computer could, in theory, read old memos. That would reveal fingerprints, never files.

So: stamp before Q, and your date stays solid. Yes, we're telling you the weak spot ourselves. That's the point.

Mini-resume

"Stamp it with Z. Before Q." refers to the future day quantum computers can break some current cryptography. A ZKStamp proof's date relies on SHA-256 and the blockchain record, expected to hold up against quantum computers. Its privacy relies on zk-SNARKs, which are not post-quantum: old memos could one day reveal fingerprints, never files.

❓ 8. What are the honest limits?

The server sees the fingerprint (and the text, for timestamp_text) when you submit it. It doesn't log them, and it doesn't store which proof belongs to which account. The code is public.
One operator, one server. If it's down, no new proofs. Existing proofs stay verifiable on any BitcoinZ node.
Block dates are approximate. Blockchains tolerate some clock drift; Bitcoin, for example, accepts block times up to two hours ahead. Think "that hour", not "that second". (Source: Wikipedia)
BitcoinZ is a small chain, with thin trading volume and concentrated mining. For a high-stakes proof, let it gather many confirmations.
Recent incident: on 21 October 2026, a validation bug in BitcoinZ's legacy Sprout pool was exploited. BitcoinZ fixed it in release 2.3.1. The ZKStamp node runs 2.3.1, and ZKStamp uses the Sapling pool, not Sprout.
Not legal advice. Whether a court or a patent office accepts a blockchain timestamp depends on the country and the case.

Mini-resume

ZKStamp's server sees each fingerprint at submission but does not log it or link proofs to accounts. A single operator runs the service, though existing proofs stay verifiable on any BitcoinZ node. Block dates are approximate to the hour. BitcoinZ is a small chain that fixed a Sprout validation bug in release 2.3.1, which the ZKStamp node runs. Legal acceptance of blockchain timestamps varies by country.

📄 Docs, code and ZCheck on GitHub

Sources

ZKStamp Proof-100 on GitHub (docs, server code, ZCheck, MIT license)
BitcoinZ explorer, demo transaction (block 1,862,988)
Wikipedia, SHA-2
Wikipedia, Trusted timestamping
Gipp, Meuschke and Gernandt, Decentralized Trusted Timestamping using the Crypto Currency Bitcoin (2015)
BitcoinZ

Keywords: proof of existence · blockchain timestamp · shielded timestamp · zero-knowledge proof · zk-SNARKs · BitcoinZ · AI agent MCP · prove when you created it · prior art · on-chain messaging solution · blockchain messenger

🔗 Also read: Signal vs Z-TEXT · WhatsApp vs Z-TEXT · Session vs Z-TEXT · Telegram vs Z-TEXT · The Third Man