Frequently asked questions

Cuvex combines offline encryption of seed phrases and other secrets with Bitcoin transaction signing through PSBT. The app prepares and communicates; the device lets you review and authorize. Encrypted backups are kept on compatible external media.

Choose Original for NFC cards read and written directly by the device. USB-C provides power; Bluetooth is reserved for firmware updates. No biometrics. Choose BIT to exchange files over USB-C with Desktop or a compatible app and add a fingerprint as an extra factor. BIT has no NFC or Bluetooth.

Cuvex BIT connects directly to Cuvex Desktop over USB-C. To fully operate Cuvex Original with Desktop, you need Cuvex Mirror on a compatible NFC smartphone, linked to your computer over Bluetooth. Mirror reads and writes NFC cards; sensitive operations are reviewed and authorized on your Cuvex device.

To reduce tampering risk, buy from the official store or an authorized distributor and check the seals. Appearance alone cannot establish the integrity of a used device. Contact support if you are unsure about its origin.

New cryptograms use AES-256-GCM authenticated encryption, checking the protected content and authentication tag. This does not mean that all metadata or every older copy has this protection.

Use a password of at least 12 characters combining uppercase and lowercase letters, numbers and symbols. The device applies a delay after incorrect attempts; follow its on-screen instructions. Choose a long, unique password and plan how to retain it without keeping it beside all your backups.

You can protect seed phrases, private keys and other text. We support BIP39, Monero and SLIP39 word selection, up to 54 words, or text up to 500 characters. A card holds one cryptogram; clearly distinguish any seed phrases grouped inside it. The required medium also depends on the encryption scheme.

Inspect the packaging and security seals before using the device. Keep their codes and validate them in the app’s traceability section. Follow your model’s manual and firmware installation flow. If you see tampering or validation fails, contact support before continuing.

Download only the file for your model. Check its integrity and follow the official app’s update procedure. Original updates over Bluetooth; BIT over USB-C.

We use the STM32U585 microcontroller in Cuvex Original. Always check the documentation for your model and revision. Ask support for the specific declaration of conformity or certificate; a component name alone does not establish product certification.

On Original, bring the card to the reading area shown in the manual, near the lower front. Try both sides and orientations, moving slowly until detected. The green LED indicates NFC detection. Keep the card still until the operation finishes.

No. Biometrics are optional and add a presence check to the required passwords. If you choose biometric protection, decryption requires Cuvex BIT. Consider your recovery plan when choosing this condition.

Our standard card uses NTAG216. The Cuvex 8K card uses MIFARE DESFire EV1 8K with NDEF formatting for threshold cryptograms requiring more capacity. A cryptogram requiring 8K cannot be cloned onto a standard card, and neither type stores BIT biometric cryptograms.

Compatible Cuvex cards come prepared for their intended workflow. Do not erase or reformat them with third-party apps before use, as this can alter their format. A matching chip or capacity on another card does not establish full compatibility.

Use an NFC diagnostic tool in read-only mode. Remove the card from its sleeve, separate it from other cards and read one at a time. Detecting NTAG216 identifies the chip, but does not alone verify formatting, usable capacity or compatibility with a Cuvex workflow.

Wait until the device confirms that reading or writing has finished. Early removal can interrupt the operation even after detection. If interrupted, follow the device’s instructions and verify the result before relying on the backup.

Remove sleeves, separate other cards and try different sides and orientations over the NFC area. Check power, card condition and compatibility. If other cards work, do not assume the reader is faulty: record which card and operation fail for support.

It does not identify a single cause. Check chip, capacity, NDEF formatting, cryptogram type and whether the destination is blank. Also check the workflow, NFC position, firmware, app and power. Phone detection does not rule out writing or compatibility issues.

Besides correct format and capacity, writing needs stable power throughout. Try the original cable and a suitable power source, avoiding unnecessary adapters. Successful startup does not rule out a cable or power issue. Record the exact step and message if it fails again.

We do not provide cryptogram erasure or overwriting. Use new media for important secrets. External tools can alter the format and destroy a secret’s only backup; do not use them on cards containing information you need to retain.

Not necessarily. In Original’s workflow that prepares text on an NFC card from the app, that temporary text is still readable. Encryption happens afterward on the device using the text-from-NFC option. To avoid entering the secret on your phone, use the device’s input.

WOW lets you view balances and history, manage accounts and addresses, and prepare transactions using public wallet information. It does not itself hold the private keys needed to sign. Treat public wallet data as sensitive too, since it can reveal financial activity.

It lets you label and select UTXOs, freeze outputs you do not want to spend, and organize funds. Keep a backup of labels if you want to restore them on another phone. These tools help operational privacy, but do not make Bitcoin transactions anonymous.

No. Chat coordinates addresses and payment requests; acceptance prepares the context. WOW builds the transaction, and you must review and sign it on the device before broadcast. Always check the address, amount and fee.

A PSBT contains information for a Bitcoin transaction that needs signing. Preparing it does not spend funds. The device reviews and signs offline; the app then broadcasts the signed transaction. This separation lets you check the operation on a dedicated screen before authorization.

Both devices process BIP174 v0 PSBTs with P2WPKH inputs and SIGHASH_ALL. They review recipients, amounts, change and fees; approval is bound to that transaction and the signature is verified. Displaying Taproot Bech32m recipients does not mean signing Taproot inputs. Private keys are not exported for signing.

Cuvex BIT connects directly to Cuvex Desktop over USB-C. To fully operate Cuvex Original with Desktop, you need Cuvex Mirror on a compatible NFC smartphone, linked to your computer over Bluetooth. Mirror reads and writes NFC cards; sensitive operations are reviewed and authorized on your Cuvex device. Both devices process BIP174 v0 PSBTs with P2WPKH inputs and SIGHASH_ALL. They review recipients, amounts, change and fees; approval is bound to that transaction and the signature is verified. Displaying Taproot Bech32m recipients does not mean signing Taproot inputs. Private keys are not exported for signing.

The guided flow produces a 24-word BIP39 seed using the 2048-word dictionary. Follow the device’s rolls and checks. The menu language does not determine the seed dictionary language.

No. Encryption protects the text of a seed or key within the input limits. Our signing function is Bitcoin PSBT. Other assets require a wallet and recovery procedure compatible with their network.

A cryptogram is the encrypted form of your secret. Copying it does not disclose the readable content, but it remains sensitive material that you should protect. Decryption requires the configured passwords and, where applicable, biometric requirements.

Follow the cloning flow: provide the source, then a compatible blank destination. Original works directly with NFC; on BIT, the app manages external media. Verify the finished copy and keep it in a separate location.

No Cuvex cryptogram is tied to a particular device. You can decrypt it on any compatible Cuvex device, provided you retain the cryptogram and its required credentials. Cryptograms protected with biometrics can only be decrypted on Cuvex BIT.

You can decrypt the secret and create a new cryptogram on another medium with new passwords or participants. Existing copies do not change or become automatically revoked. Review which copies and access conditions remain before considering your plan updated.

No. Protect decryption with up to six participants, requiring everyone or a threshold such as 2 of 3. This policy controls access to the secret; it does not turn a wallet into a Bitcoin multisig wallet.

No. Protect decryption with up to six participants, requiring everyone or a threshold such as 2 of 3. This policy controls access to the secret; it does not turn a wallet into a Bitcoin multisig wallet.

Without biometrics, a cryptogram requiring all participants can use standard cards or USB drives through the compatible workflow. Thresholds with optional participants require an 8K card or USB drive. BIT biometric cryptograms use external USB-C drives connected to the phone, never NFC cards.

Recovery depends on retaining a valid cryptogram and its credentials. Use a device compatible with that format; biometric cryptograms require BIT. Desktop can be an emergency alternative for compatible formats without biometrics. Test your procedure before you need it.

Cuvex does not keep your passwords to reconstruct them. If the configured threshold can still be met by other participants, follow that procedure. If essential credentials are missing, do not rely on the device, biometrics or support to replace them.

An encrypted copy does not directly disclose the secret, but review any exposure of its passwords and your recovery plan. Keep verified backups in separate locations. If you suspect the secret or credentials are compromised, consider creating a new wallet and transferring funds through a safe procedure.

Create verified copies, label media without writing secrets and distribute them across locations. The case adds organization and radiofrequency shielding when properly closed; effectiveness depends on condition and frequency. It does not replace encryption, passwords or recovery checks.

Reinstall the official app and relink public wallet information and media following the manual. Labels and other local data need their own backups. Reinstalling the app is not the same as recovering the secret: retain valid cryptograms and credentials separately.

Cuvex BIT connects directly to Cuvex Desktop over USB-C. To fully operate Cuvex Original with Desktop, you need Cuvex Mirror on a compatible NFC smartphone, linked to your computer over Bluetooth. Mirror reads and writes NFC cards; sensitive operations are reviewed and authorized on your Cuvex device.

Cuvex Chat lets you share encrypted cryptograms through its end-to-end encrypted communication. The copy still requires its passwords and decryption conditions. Do not send readable seed phrases, private keys or passwords in chat, even if someone claims to be support.

Transcend proposes an inheritance plan using encrypted backups, separate passwords and configurable proof-of-life checks. Ask sato@cuvex.io about current availability and terms before relying on the service. Technical access planning should be coordinated with your country’s inheritance requirements.

Our model starts with a cryptogram requiring at least two passwords. Heirs receive a copy and one password; another is protected through Transcend for release under the planned conditions. The copy alone is insufficient. Confirm the procedure and terms before activation.

You can edit or cancel your plan and manage primary cards by following our current procedure. Lost cards, stolen copies or forgotten passwords require reviewing recovery conditions; do not assume cancelling a service erases existing copies. Ask for the current procedure to renew the plan and access arrangements.

There is no such guarantee. Our design combines local encryption, Shamir splitting and distributed encryption nodes to protect the service-managed password. Retain the other credentials and copies, review availability requirements, and check that your heirs understand the procedure.

Install our official app using the link on our website and check compatibility with your model. BIT requires an iPhone with USB-C and a suitable data cable. For NFC workflows, check that your phone supports the required operation and follow the permissions requested by iOS.

Email sato@cuvex.io with your iPhone model, iOS version, app version, Cuvex model and firmware. Include the exact step and message; for USB-C, also identify the cable and adapters. Do not send seed phrases, private keys or passwords.

Install our official app using the link on our website and check your model’s requirements. Enable NFC when the workflow needs it and grant the requested Bluetooth or USB permissions. For BIT, use a USB-C data cable, not a charge-only cable.

Check that you are using our official app, maintain power and follow the bootloader workflow. If it is interrupted again, record the phone model, Android, app and firmware versions and contact us. You can try updating with another compatible smartphone; never share secrets for diagnosis.

It is the application for organizing cryptograms and encrypted backups, watching Bitcoin accounts through public descriptors, and connecting your computer to Cuvex Original or BIT.

We publish the available Linux, macOS and Windows downloads on this page. Choose the package for your system and architecture: x64 or ARM64, or Intel and Apple Silicon on Mac. Availability and format depend on the published release; read its details before downloading.

Cuvex Mirror uses your compatible smartphone’s NFC to read and write cards for Cuvex Desktop through an encrypted Bluetooth connection. It is required to fully operate Cuvex Original with Desktop. Mirror does not decrypt your secrets or replace authorization on the hardware.

DESFire EV1 8K with public NDEF Type 4 and NTAG216 prepared for public NDEF Type 2. Format, permissions and capacity must suit the content. Desktop does not format unknown cards or access DESFire applications protected by keys.

Read, link and clone compatible cards from Desktop with Cuvex Mirror. Before writing, the app checks the destination, protects recognized Cuvex cryptograms and verifies the write by reading it back. Use a dedicated 8K card for PSBT and always retain the original.

Connect BIT over USB-C and select its CUVEX volume or Cuvex folder when Desktop asks. The application handles its cryptogram, PSBT and firmware requests. Review and authorize sensitive operations on BIT.

A lost or damaged Cuvex should not leave you without an alternative when you cannot wait for another device. Desk can locally decrypt a compatible non-biometric copy if you retain the passwords required by the cryptogram. This feature exposes the secret on your computer, outside the isolation of Cuvex hardware. Malware, a malicious administrator or a screen capture can compromise it even without Internet access. Neither the timer nor disconnection guarantees absolute safety. Decryption does not take place on this website or through support.

A WOW watches a Bitcoin account through its public descriptor. It derives addresses, shows activity and prepares PSBTs. Import the complete descriptor and verify it on the device. Do not enter seeds or private keys.

Balance, address, fee and transaction functions are for Bitcoin on mainnet, testnet and signet. You can organize cryptograms for other purposes, but this beta does not provide a transaction wallet for every cryptocurrency.

Desktop prepares the PSBT for a compatible device. Review and authorize it on the device screen. Desktop verifies the returned signature and asks for final confirmation before broadcasting. Compatibility also depends on firmware and account profile.

Backups and local NFC/USB operations can run without consulting Internet services. Balances, activity, fees, transaction broadcasting, exchange rates, chat and firmware checks or downloads need access to their respective services. Disconnect the computer from the Internet and networks. Use a computer you control, close remote access and follow Desk’s disconnection check. Being offline does not clean an infected computer.

Yes, a compatible Bitcoin Core node that you authorize. Desktop imports public descriptors into a watch-only wallet without private keys. Public providers receive derived addresses, not the account descriptor; they can link queries, IP addresses and broadcast transactions.

In an encrypted local vault protected by a password. The global backup includes cryptograms, WOWs, labels, drafts and settings; chat and biometric authorization are excluded. Keep the backup and password safe. Restoring replaces the current local contents.

It is optional: Touch ID on Mac, Windows Hello on Windows and fprintd on Linux, subject to hardware and secure-store availability. Password access remains available. This beta does not certify every physical sensor.

Desktop checks for and downloads official firmware. Original receives it over Bluetooth and BIT over USB-C. Keep power and the connection stable and check the final version on the device. If interrupted, restart the flow on Cuvex before retrying.

Download the new package, check its SHA-256, create an encrypted global backup and fully close the previous version before replacing it. Updating preserves the vault; you do not need to restore a backup over your data.

Spanish, English, French, Italian, Portuguese, German, Turkish, Japanese, Korean, Polish, Russian and Arabic. Translations are bundled with the application; Arabic uses right-to-left text. Chat messages retain their original language.

We are continuing to improve this beta. Software and package tests do not physically validate every combination of device, smartphone running Cuvex Mirror, card and system. Keep verified backups and check your setup before important operations. Some features require external services.

Email sato@cuvex.io with the version, operating system, architecture, device and firmware, smartphone running Cuvex Mirror, steps and observed result. You can attach the diagnostic report from Security. Never send seeds, private keys, passwords or your Chat Key.

You need Android 8 or later with NFC, a camera and Bluetooth peripheral mode, plus a computer with compatible Bluetooth and Cuvex Desk. A temporary PIN and QR bind the session. Mirror needs no account or Internet permission and does not decrypt your secrets.

You need the complete, compatible cryptogram and the password or number of passwords required by its multisignature scheme. It cannot recover forgotten passwords or rebuild lost data. Cryptograms protected by biometrics require the compatible device and cannot be decrypted on the PC.

Disconnect the computer from the Internet and networks. Use a computer you control, close remote access and follow Desk’s disconnection check. Being offline does not clean an infected computer. Use the emergency window in the official app. The secret is displayed for 45 seconds, with up to three extensions within the session limit. Do not take screenshots or share the secret, passwords or file with support, chats or online services. When finished, close the flow and return to secure hardware for normal use. If you exposed a seed phrase, plan to move the funds to a new wallet generated on a trusted device. Forensic erasure of the computer is not guaranteed.

The store offers Bitcoin through BTCPay Server and USDC through Cuvex SCP when enabled. Reference prices are in USD. Use only the invoice or payment request generated for your order and check the asset, network, amount and expiry before sending.

When the system verifies the invoice payment and its confirmation conditions. Returning to the store or seeing a sent transaction does not itself confirm the order. Check its status; if the amount, expiry or confirmation raises questions, contact support with the order reference.

Send only the USDC and network specified in your order’s active payment request. Do not assume another network or token is equivalent. If the quote expires, return to the order for current instructions before paying; do not independently reuse an old address or request.

In this store, the final price includes taxes, shipping and customs duties for an order accepted by checkout. Check the total before confirming. If a carrier requests an additional charge, contact support with your order reference so it can be reviewed.

Checkout shows available destinations and delivery information for your order. Timing depends on destination, preparation and transport; use the estimate communicated for your purchase. Check order status and tracking to follow its progress.

Use the order access and documents provided by the store. If you need additional tax details or a named invoice, email sato@cuvex.io with the order reference and necessary billing information. We may verify your access before providing personal information.

Personalized cards use PNG or JPG images: one image for both sides or two for a different design on each side. Never include secrets in the artwork. Cuvex Expert is a 60-minute online session in Spanish or English for device owners; the team coordinates scheduling without needing your keys.

Email sato@cuvex.io with the order reference and a description of the issue. Check the current policy for coverage, time limits and the procedure applicable to your purchase. Accidental damage and a manufacturing defect may be handled differently. Request instructions before sending anything and do not include media containing secrets.

Email sato@cuvex.io with device and phone models, system, app and firmware versions, card and cryptogram type, operation, error and exact step. For writing failures, include the cable and power source used. Never share seed phrases, private keys, passwords, fingerprints or screenshots showing secrets.

New cryptograms use AES-256-GCM authenticated encryption, checking the protected content and authentication tag. This does not mean that all metadata or every older copy has this protection.

No. Protect decryption with up to six participants, requiring everyone or a threshold such as 2 of 3. This policy controls access to the secret; it does not turn a wallet into a Bitcoin multisig wallet.

Both devices process BIP174 v0 PSBTs with P2WPKH inputs and SIGHASH_ALL. They review recipients, amounts, change and fees; approval is bound to that transaction and the signature is verified. Displaying Taproot Bech32m recipients does not mean signing Taproot inputs. Private keys are not exported for signing.

Three attempts trigger a five-minute pause that persists after power loss. This limits attempts on the device, not offline attacks on an exported copy. Use strong credentials and protect your backups.

After decrypting a compatible older unauthenticated copy, create a reinforced version while retaining the secret, credentials and participant policy. Original saves it to NFC; BIT returns it over USB-C and retains biometric templates where applicable. Verify the new copy before retiring the old one.

The guided flow produces a 24-word BIP39 seed using the 2048-word dictionary. Follow the device’s rolls and checks. The menu language does not determine the seed dictionary language.

No Cuvex cryptogram is tied to a particular device. You can decrypt it on any compatible Cuvex device, provided you retain the cryptogram and its required credentials. Cryptograms protected with biometrics can only be decrypted on Cuvex BIT.

Cuvex BIT connects directly to Cuvex Desktop over USB-C. To fully operate Cuvex Original with Desktop, you need Cuvex Mirror on a compatible NFC smartphone, linked to your computer over Bluetooth. Mirror reads and writes NFC cards; sensitive operations are reviewed and authorized on your Cuvex device.