Backing Up Seed Phrases with SeedSafe¶

Time Required: 10-15 minutes Difficulty: Beginner Tier Required: Sovereign or HighRisk

SeedSafe provides military-grade protection for your cryptocurrency seed phrases using split-entry protocols, quadruple encryption, and zero-knowledge storage. This guide walks you through the complete setup process.

What You'll Achieve¶

By the end of this guide, your seed phrase will be:

✅ Encrypted with four layers of protection
✅ Stored with zero-knowledge (UnoLock can't see it)
✅ Protected against quantum computing threats
✅ Backed up across multiple geographic regions
✅ Recoverable if you lose your devices
✅ Inheritable through LegacyLink (if configured)

Prerequisites¶

Before you begin, ensure you have:

An UnoLock account on Sovereign or HighRisk tier
Your seed phrase written down (temporarily—you'll secure it properly)
A device with FIDO2/biometric authentication set up
10-15 minutes of uninterrupted time
Privacy—no one should see your screen during this process

Security First

Never enter your seed phrase on a compromised device. If you suspect malware, use a different device or factory reset first.

Understanding SeedSafe's Security Model¶

Before we begin, understand why SeedSafe is different:

Split-Entry Protocol¶

You enter your seed phrase in two halves (e.g., words 1-12 and 13-24). This means: - Even if one entry session is compromised, attackers only get half - You can enter each half on different devices for extra security - Neither half alone can access your funds

Quadruple Encryption¶

Your seed phrase is protected by four encryption layers: 1. Your PIN — Something you know 2. Your FIDO2/biometric key — Something you have/are 3. Client-side AES-256-GCM — Industry-standard encryption 4. Post-quantum algorithms (Kyber) — Future-proof protection

Zero-Knowledge Storage¶

UnoLock servers receive only encrypted blobs. We cannot: - See your seed phrase - Know what cryptocurrency it's for - Connect the two halves together - Decrypt anything, ever

Step-by-Step Guide¶

Step 1: Access Your Vault¶

Navigate to safe.unolock.com
Authenticate using your FIDO2 key or biometric
Enter your PIN when prompted

Use a Clean Browser

For maximum security, use a private/incognito window with no extensions, or use UnoLock's dedicated PWA.

Step 2: Navigate to SeedSafe¶

From the main dashboard, select your Safe
Navigate to the SeedSafe section
Click "Add New Seed Phrase"

You'll see options for: - 12-word phrase (128-bit entropy) - 18-word phrase (192-bit entropy) - 24-word phrase (256-bit entropy)

Select the option matching your seed phrase length.

Step 3: Enter First Half of Seed Phrase¶

You'll be prompted to enter the first half of your seed phrase
For 12 words: Enter words 1-6
For 24 words: Enter words 1-12
Enter each word carefully in the correct order
SeedSafe validates each word against the BIP-39 wordlist in real-time
Valid words show a ✓
Invalid words are highlighted for correction
Click "Continue" when the first half is complete

Real-Time Validation

SeedSafe checks that each word exists in the official BIP-39 wordlist. This prevents typos from corrupting your backup.

Step 4: Re-authenticate¶

For security, you must re-authenticate before entering the second half:

Complete FIDO2/biometric authentication
Enter your PIN

This ensures that even if someone grabbed your device during the first half entry, they can't complete the process.

Step 5: Enter Second Half of Seed Phrase¶

Enter the second half of your seed phrase
For 12 words: Enter words 7-12
For 24 words: Enter words 13-24
Validate each word as before
Click "Complete"

Step 6: Checksum Verification¶

SeedSafe now performs BIP-39 checksum verification:

The system mathematically verifies your complete seed phrase
If valid, you'll see a green confirmation
If invalid, you'll be prompted to review your entries

Checksum Failed?

If verification fails, one or more words may be incorrect. Carefully compare against your written backup. The most common errors are similar-looking words (e.g., "word" vs "work").

Step 7: Confirm Storage¶

Review the confirmation screen showing:

Seed phrase type (12/18/24 words)
Encryption status (quadruple encryption active)
Storage location (your selected Space, if using Spaces)
Redundancy status (multi-region backup enabled)

Click "Confirm and Encrypt" to finalize.

Step 8: Secure Your Physical Backup¶

Now that your seed phrase is securely stored in SeedSafe:

Verify recovery works (see next section)
Then securely destroy your paper backup
Burn or shred—don't just throw away
Ensure no photos or copies exist anywhere

Don't Skip Verification

Never destroy your physical backup until you've confirmed you can recover from SeedSafe. Test the recovery process first.

Verifying Your Backup¶

Always verify that recovery works before relying on SeedSafe as your only backup.

To Verify:¶

Navigate to your stored seed phrase in SeedSafe
Select "View Seed Phrase"
Re-authenticate (FIDO2 + PIN)
You'll see the first half displayed
Re-authenticate again for the second half
Compare against your physical backup—they should match exactly

Annual Verification

Set a calendar reminder to verify your SeedSafe backup annually. Confirm you can still access it and that recovery procedures work.

Advanced: Using Split-Device Entry¶

For maximum security, enter each half on a different device:

Why Split-Device?¶

If Device A is compromised, attacker only gets half your phrase
Neither device ever sees the complete seed phrase
Requires compromise of two separate devices to attack

How to Use Split-Device Entry:¶

Start SeedSafe setup on Device A
Enter the first half of your seed phrase
Complete the first-half encryption
On Device B, log into the same UnoLock account
Navigate to the pending SeedSafe entry
Enter the second half of your seed phrase
Complete the process

Both halves are stored encrypted, and neither device ever processed the complete phrase.

Storing Multiple Seed Phrases¶

SeedSafe supports multiple seed phrases for different wallets:

Using Spaces for Organization¶

If you have Spaces enabled (Sovereign/HighRisk tier):

Create separate Spaces for different purposes:
"Bitcoin Cold Storage"
"Ethereum DeFi"
"Hardware Wallet Backup"
Store each seed phrase in its appropriate Space
Configure different access controls per Space if needed

Without Spaces¶

You can store multiple seed phrases in your default vault. Use clear labels to identify each:

"Ledger Nano X - BTC/ETH"
"MetaMask - DeFi wallets"
"Trezor - Long-term storage"

Troubleshooting¶

"Word not recognized"¶

Cause: The word isn't in the BIP-39 wordlist, or there's a typo.

Solution: - Check spelling carefully - Common confusions: "word/work", "letter/latter", "first/fist" - Refer to the official BIP-39 wordlist

"Checksum verification failed"¶

Cause: One or more words are incorrect, or words are in wrong order.

Solution: - Verify each word against your physical backup - Confirm the order is correct (word 1, word 2, etc.) - Try re-entering both halves carefully

"Authentication failed during second half entry"¶

Cause: Session timeout or FIDO2 key issue.

Solution: - Ensure your FIDO2 key is properly connected - Try again—the first half is saved and encrypted - If persistent, check your FIDO2 key batteries (if applicable)

"Can't see my stored seed phrase"¶

Cause: May be stored in a different Space, or viewing permissions.

Solution: - Check all Spaces if you have multiple - Ensure you're logged in with the correct credentials - Verify you have view permissions if using shared access

Security Best Practices¶

Do ✅¶

Use split-device entry for high-value seed phrases
Verify recovery before destroying physical backups
Use a clean, private browser session
Complete the process in one sitting when possible
Set up LegacyLink for inheritance

Don't ❌¶

Enter seed phrases on public/shared computers
Take screenshots during the process
Share your screen while entering seed phrases
Rush through—accuracy matters more than speed
Store seed phrases without testing recovery

Next Steps¶

Set Up LegacyLink

Ensure your heirs can access your crypto if something happens to you.

LegacyLink Guide
Configure DuressDecoy

Protect against coercion by hiding sensitive Spaces behind a safeword PIN.

Privacy Guides
Add More Security

Learn about Spaces, TimeLock, and other features.

How-To Guides
Get Support

Questions? We're here to help.

Reddit Community

Seed Phrase Security: The Complete Guide — Understand the risks
Setting Up LegacyLink — Inheritance planning
Using Spaces for Organization — Compartmentalize your data

Your seed phrase is now protected with military-grade encryption, zero-knowledge storage, and post-quantum security. Sleep better knowing your crypto is safe.