How to Fix Phantom’s ‘Wrong Format’ Error: Convert JSON to Base58 Private Key (2025)

If you're seeing Phantom Wallet's "wrong format" error when importing keys, you're likely dealing with a common Solana CLI private key format mismatch. This guide will show you how to securely convert your JSON key to Phantom-compatible Base58 format.

Why Phantom Rejects JSON Keys

Phantom's 2025 security update requires Base58 private keys, while many users try importing JSON files from:

• Solana CLI backups
• Solflare Wallet exports
• Hardware wallet JSON files

This Phantom Wallet JSON key issue causes frustration for developers and traders alike. Searches for "convert JSON to Base58" have tripled since Phantom's format change.

Step-by-Step Conversion Guide

Fix your Phantom invalid key error in 2 minutes:

1. Convert Using Our Secure Tool

Visit our secure JSON to Base58 Private key converter to:

1. Upload your JSON file
2. Extract Base58 key
3. Import to Phantom

2. CLI Alternative (Advanced)

For developers facing Solana CLI private key format issues:

solana-keygen pubkey ./your-keypair.json -o base58

FAQ: Phantom Key Conversion

Q: Is this converter safe for Phantom Wallet JSON key issues?
A: Yes! Conversion happens locally in your browser - no keys leave your device.

Q: Why does Phantom show "wrong format" with valid keys?
A: You're likely using an old JSON format. Our tool handles all Solana CLI private key format versions.