Documented final-word compatibility

What inclusion means

A record is included only when a current primary source documents final-word calculation or checksum-valid selection after 11 or 23 user-supplied English BIP39 words. Ordinary import or checksum validation of an already-complete phrase does not qualify.

Inclusion establishes documented behavior only. HAT39 has not audited or endorsed the security of any listed wallet, firmware, hardware, operating environment, or third-party tool.

The HAT39 convention

“HAT39 first” means the checksum-valid final word with the lowest index in the official English BIP39 list. Some tools implement the zero-suffix path directly; others expose candidates and require a deliberate manual choice. A tool that adds random final-word entropy is not HAT39-first compatible.

Review the exact bit construction →

Device or tool	12 words	24 words	HAT39 convention	Primary evidence
SeedSignerDIY signer	Yes	Yes	Native HAT39 first Tools → Calc final word → enter 11 or 23 words → choose Finalize with zeros. Method and offline posture Offers coin flips, word-selection entropy, or a deterministic Finalize with zeros path after 11 or 23 entries. Air-gapped Raspberry Pi Zero signer with no wireless hardware in the recommended build.	SeedSigner custody guide ↗Checked 2026-08-11
COLDCARD Mk4 / QHardware wallet	Yes	Yes	Choose first manually Choose the candidate with the lowest official BIP39 index. Method and offline posture Exposes every valid candidate after 11 or 23 entries; 12-word candidates are grouped by first letter. Can be operated without USB data; Q also supports QR and MicroSD workflows.	COLDCARD master-seed guide ↗Checked 2026-08-11
KruxDIY signer	Yes	Yes	Choose first manually Manually choose the valid candidate with the lowest official list index. Method and offline posture Restricts the final-word keypad to valid candidates; leaving it blank selects a candidate randomly. Open-source signer firmware for standalone camera devices.	Krux mnemonic-generation guide ↗Checked 2026-08-11
Passport CoreHardware wallet	Yes	Yes	Random final entropy Do not use Passport as the HAT39 final-word calculator. It can import a completed HAT39 phrase calculated elsewhere. Method and offline posture Generate Final Word samples device noise and calculates one valid ending; retrying samples again. Designed for QR and microSD air-gapped operation.	Foundation Passport setup guide ↗Checked 2026-08-11
Blockstream JadeHardware wallet	Yes	Yes	Choose first manually Do not accept the randomized default; choose the lowest-index valid candidate. Method and offline posture Restricts final-word entry to valid options; its starting keyboard letter and initial candidate are randomized. Jade Plus supports QR air-gap; other models can use a temporary signer workflow.	Blockstream final-word guide ↗Checked 2026-08-11
SeedPicker Last WordOffline browser tool	No	Yes	Native HAT39 first Download and verify the tool, disconnect, then run it in a disposable offline environment. Method and offline posture Its 24-word calculator returns the alphabetically first, lowest-index valid ending. Web code must be downloaded, audited as desired, disconnected, then run locally.	SeedPicker guide ↗Checked 2026-08-11
Coinplate BIP39 RecovererOffline browser tool	Yes	Yes	Choose first manually Take the listed candidate with the lowest official BIP39 index. Method and offline posture Tests the official list from index 0 upward and displays all valid candidates when the final position is a question mark. Download the standalone HTML and run it on a fresh offline system.	Coinplate source repository ↗Checked 2026-08-11

Device or tool

12 words

24 words

HAT39 convention

Primary evidence

SeedSignerDIY signer

Yes

Native HAT39 first

Tools → Calc final word → enter 11 or 23 words → choose Finalize with zeros.

Method and offline posture

Offers coin flips, word-selection entropy, or a deterministic Finalize with zeros path after 11 or 23 entries.

Air-gapped Raspberry Pi Zero signer with no wireless hardware in the recommended build.

SeedSigner custody guide ↗Checked 2026-08-11

COLDCARD Mk4 / QHardware wallet

Yes

Choose first manually

Choose the candidate with the lowest official BIP39 index.

Method and offline posture

Exposes every valid candidate after 11 or 23 entries; 12-word candidates are grouped by first letter.

Can be operated without USB data; Q also supports QR and MicroSD workflows.

COLDCARD master-seed guide ↗Checked 2026-08-11

KruxDIY signer

Yes

Choose first manually

Manually choose the valid candidate with the lowest official list index.

Method and offline posture

Restricts the final-word keypad to valid candidates; leaving it blank selects a candidate randomly.

Open-source signer firmware for standalone camera devices.

Krux mnemonic-generation guide ↗Checked 2026-08-11

Passport CoreHardware wallet

Yes

Random final entropy

Do not use Passport as the HAT39 final-word calculator. It can import a completed HAT39 phrase calculated elsewhere.

Method and offline posture

Generate Final Word samples device noise and calculates one valid ending; retrying samples again.

Designed for QR and microSD air-gapped operation.

Foundation Passport setup guide ↗Checked 2026-08-11

Blockstream JadeHardware wallet

Yes

Choose first manually

Do not accept the randomized default; choose the lowest-index valid candidate.

Method and offline posture

Restricts final-word entry to valid options; its starting keyboard letter and initial candidate are randomized.

Jade Plus supports QR air-gap; other models can use a temporary signer workflow.

Blockstream final-word guide ↗Checked 2026-08-11

SeedPicker Last WordOffline browser tool

Yes

Native HAT39 first

Download and verify the tool, disconnect, then run it in a disposable offline environment.

Method and offline posture

Its 24-word calculator returns the alphabetically first, lowest-index valid ending.

Web code must be downloaded, audited as desired, disconnected, then run locally.

SeedPicker guide ↗Checked 2026-08-11

Coinplate BIP39 RecovererOffline browser tool

Yes

Choose first manually

Take the listed candidate with the lowest official BIP39 index.

Method and offline posture

Tests the official list from index 0 upward and displays all valid candidates when the final position is a question mark.

Download the standalone HTML and run it on a fresh offline system.

Coinplate source repository ↗Checked 2026-08-11