Is it safe to enter a seed phrase?

Only in a client-side tool. Verify in DevTools → Network: no outbound requests should fire when you enter sensitive data.

Do these tools provide financial advice?

No. Calculators illustrate mechanics and estimates — not financial advice.

Crypto Tools

Brevio crypto tools run entirely in your browser. No address, seed phrase, or transaction data ever leaves your device.

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APY ↔ APR Calculator

Convert between APR and APY with any compounding frequency. See how compounding frequency affects yield instantly. Free, private.

Crypto ToolsNew

BIP39 Seed Phrase Validator

Validate 12 or 24-word BIP39 seed phrases. Check each word against the official wordlist, validate checksums, and get suggestions for typos. Runs entirely in your browser.

Crypto ToolsNew

Bitcoin Address Validator

Validate Bitcoin addresses in your browser. Supports P2PKH, P2SH, Bech32, and Taproot. Checksum verified locally — address never leaves your device.

Crypto ToolsNew

Crypto Denomination Reference

Reference table for Bitcoin (satoshi → BTC), Ethereum (wei → ETH), and Solana (lamport → SOL) units. Optionally enter a price to see USD values.

Crypto ToolsNew

Crypto Payment QR Generator

Generate Bitcoin, Ethereum, Solana, or Litecoin payment QR codes using standard URI schemes (BIP-21, EIP-681). Download as PNG. Runs in your browser.

Crypto ToolsNew

Crypto Tax P&L Calculator

Calculate realized crypto gains using FIFO cost basis. Enter buy and sell transactions, get short-term vs. long-term P&L, and export to CSV. Not tax advice.

Crypto ToolsNew

DCA Calculator

Simulate dollar-cost averaging investments. Plan recurring purchases, track cumulative cost basis, and visualize your DCA schedule over time. Purely illustrative — no price data.

Crypto ToolsNew

ETH Unit Converter

Convert between wei, kwei, mwei, gwei, szabo, finney, and ETH. Optionally add a price for USD value. Client-side, private.

Crypto ToolsNew

Ethereum Address Validator

Validate Ethereum addresses and generate EIP-55 checksums instantly. Free, private, no upload.

Crypto ToolsNew

Portfolio Rebalancer

Enter your current holdings and target allocations to see what to buy or sell to rebalance. Calculates drift and required trades. Runs in your browser.

Crypto ToolsNew

Satoshi / BTC Converter

Convert between satoshi, bits, mBTC, and BTC instantly. Optionally enter a BTC price to see USD value. Everything runs in your browser.

Crypto ToolsNew

Staking Rewards Calculator

Estimate staking rewards over any period. Enter stake amount, APY, and compound frequency to see total rewards and month-by-month growth.

Crypto ToolsNew

Text Encryptor

Encrypt and decrypt text using AES-256-GCM with PBKDF2 key derivation, entirely in your browser. No upload, no server, no account — your text and password never leave your device.

Frequently Asked Questions

Is it safe to enter a seed phrase?: Only in a client-side tool. Verify in DevTools → Network: no outbound requests should fire when you enter sensitive data.
Do these tools provide financial advice?: No. Calculators illustrate mechanics and estimates — not financial advice.

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