Home›Validators›Security›Bitcoin / Ethereum Address Validator

Bitcoin / Ethereum Address Validator

Security

Validate Bitcoin (P2PKH, P2SH, Bech32) and Ethereum addresses instantly. Checks address format, length, and character set. Free, client-side — no data stored.

Reviewed by the thecalcu.com team · Last updated July 3, 2026

What is a Crypto Address?

A Bitcoin and Ethereum address validator checks whether a given cryptocurrency wallet address follows the correct structural format for its blockchain network. It detects the address type automatically, Bitcoin P2PKH (Legacy), P2SH (SegWit-compatible), or Bech32 (Native SegWit), or Ethereum's standard hex format, and confirms the format is valid.

Cryptocurrency wallet addresses are the public identifiers you share to receive funds. Unlike a bank account number, there is no central registry that issues addresses, they are derived mathematically from a private key. This means it is possible to type a syntactically valid-looking but incorrect address and have it accepted by a wallet interface. Sending funds to a wrong but validly formatted address results in permanent, unrecoverable loss. Address validation is the first line of defence.

Bitcoin has three active address formats in wide use. Legacy P2PKH addresses begin with 1 and use Base58Check encoding. P2SH addresses begin with 3 and are compatible with SegWit scripts. Bech32 (Native SegWit) addresses begin with bc1 and are the most efficient format, used by default in modern wallets. Ethereum uses a single format: 0x followed by 40 hexadecimal characters, optionally with EIP-55 checksum capitalisation.

The validator detects the format automatically based on the prefix and character set, so you do not need to know which type you are entering. It also notes whether an Ethereum address uses EIP-55 mixed-case checksumming, which provides an additional layer of error detection beyond the basic format check. Use it before sending any transaction to confirm the address you were given is at least structurally correct.

Why Use a Cryptocurrency Address Validator?

Cryptocurrency transactions are irreversible. There is no chargeback, no dispute resolution, and no customer support line. A mistyped or malformed address that still passes the format check may belong to a random unknown wallet, and those funds are gone. A format check is the minimum due diligence before any transaction.

The validator is also useful for developers integrating payment processing: confirm format validity client-side before submitting an address to a blockchain API, saving unnecessary API calls and providing instant feedback to users who paste incorrectly formatted addresses.

Who Should Use This Validator?

Cryptocurrency users making a payment or transfer can paste the recipient address here as a quick sanity check before confirming the transaction in their wallet.

E-commerce and freelance professionals accepting cryptocurrency payments can validate customer-provided wallet addresses before invoicing or marking an order as paid.

Developers building blockchain payment integrations, NFT platforms, or DeFi applications need address format validation as a standard input check in their user-facing forms.

Finance and compliance teams at companies with crypto treasury operations can validate wallet addresses in their records as part of counterparty due diligence.

What Insights Does the Cryptocurrency Address Validator Give You?

A valid result identifies the address type (Bitcoin P2PKH, P2SH, or Bech32; Ethereum checksummed or lowercase) and notes the relevant blockchain. For Ethereum addresses, it also notes that the address is valid on all EVM-compatible chains, useful context for users who may be sending to a Polygon or Arbitrum address using the same Ethereum address format.

An invalid result explains why: the prefix does not match any known format, the length is wrong, or the character set contains characters not valid for the detected format.

How to use this Crypto Address calculator

  1. Copy the wallet address from the recipient's wallet, payment request, or invoice.
  2. Paste it into the Crypto Address field.
  3. The result shows immediately: the detected address type and a Valid or Invalid badge.
  4. If valid, also verify the network, the same address format may be valid on multiple chains.
  5. For Bitcoin, also confirm whether the recipient's wallet supports the address format (some older wallets do not support Bech32).
Show formula & methodology ↓Show less ↑

Formula & Methodology

Bitcoin P2PKH detection:
- Starts with 1
- 25–34 characters
- All characters in the Base58 alphabet: 123456789ABCDEFGHJKLMNPQRSTUVWXYZabcdefghijkmnopqrstuvwxyz

Bitcoin P2SH detection:
- Starts with 3
- 25–34 characters
- All characters in the Base58 alphabet

Bitcoin Bech32 detection:
- Starts with bc1
- 6–90 characters after bc1
- All characters in Bech32 charset: ac-hj-np-z02-9

Ethereum detection:
- Starts with 0x
- Exactly 40 hex characters after 0x (case-insensitive)
- EIP-55: mixed case detected when letters are neither all upper nor all lower

Valid examples:
- 1A1zP1eP5QGefi2DMPTfTL5SLmv7Divfna, Bitcoin P2PKH (Genesis block)
- bc1qar0srrr7xfkvy5l643lydnw9re59gtzzwf5mdq, Bitcoin Bech32
- 0xde0B295669a9FD93d5F28D9Ec85E40f4cb697BAe, Ethereum (EIP-55)

Related Tools

You may also find these useful: JWT Validator, Password Strength Checker.

Frequently Asked Questions

What is a Bitcoin or Ethereum address validator?
A Bitcoin or Ethereum address validator checks whether a given cryptocurrency wallet address follows the correct format for its network. For Bitcoin, it validates P2PKH (Legacy), P2SH (SegWit-compatible), and Bech32 (Native SegWit) address formats. For Ethereum, it validates the 0x-prefixed 40-character hexadecimal format.
What Bitcoin address formats are supported?
Three Bitcoin address formats are supported: P2PKH addresses starting with 1 (Legacy, 25–34 characters, Base58 encoded), P2SH addresses starting with 3 (SegWit-compatible, 25–34 characters), and Bech32 addresses starting with bc1 (Native SegWit, 42 characters for P2WPKH or 62 for P2WSH). Testnet addresses are also recognised.
What does a valid Ethereum address look like?
A valid Ethereum address starts with 0x followed by exactly 40 hexadecimal characters (digits 0–9 and letters A–F, case-insensitive). A total of 42 characters. EIP-55 checksummed addresses use mixed case for the hex letters, the validator detects whether the address uses checksummed or plain lowercase format.
Does a valid address format mean the address holds funds or is active?
No. This validator checks only that the address follows the correct structural format. It cannot check the balance, transaction history, or whether the address has ever been used. A structurally valid address could belong to anyone or no one, format validity is a necessary but not sufficient condition for a real, funded wallet.
Can I use an Ethereum address on other EVM-compatible chains?
Yes. Ethereum addresses are valid on all EVM-compatible blockchain networks including Polygon, BNB Smart Chain, Avalanche C-Chain, Arbitrum, Optimism, and others. The same 0x + 40 hex character format is used across the EVM ecosystem. Always verify you are sending to the correct network, the same address exists on every EVM chain, but assets are chain-specific.
What is the difference between a P2PKH and a Bech32 Bitcoin address?
P2PKH (Legacy) addresses start with 1 and use Base58Check encoding, they are the original Bitcoin address format. Bech32 addresses start with bc1 and use a newer encoding optimised for lower error rates and QR code efficiency. Bech32 addresses also enable Native SegWit transactions, which have lower fees than Legacy transactions. Most modern wallets default to Bech32.
Does the validator perform a full checksum verification on Bitcoin addresses?
The validator performs format-level checks: length, prefix, and character set (Base58 for P2PKH/P2SH, Bech32 character set for bc1 addresses). It does not perform a full Base58Check decode with SHA256 double-hash checksum verification. A format-valid address could still have an invalid Base58Check checksum, but this is rare with correctly generated addresses.
Is my wallet address stored or uploaded anywhere?
No. All validation happens in your browser. Your address is never transmitted to a server or stored. Cryptocurrency addresses are public by design, they can be shared freely, but we still process everything locally.
What is EIP-55 and how does it relate to Ethereum addresses?
EIP-55 is an Ethereum Improvement Proposal that defines a checksum encoding for Ethereum addresses using mixed upper and lower case letters. An EIP-55 checksummed address has specific letters capitalised based on the Keccak hash of the lowercase address. The validator detects whether an address uses EIP-55 checksum and notes it in the result.
Can this validator check Litecoin, Dogecoin, or other altcoin addresses?
The validator is designed for Bitcoin and Ethereum addresses specifically. Litecoin addresses (starting with L or M), Dogecoin addresses (starting with D), and other altcoin formats are not explicitly supported. However, P2SH Bitcoin addresses (starting with 3) and Litecoin P2SH addresses (starting with M) may appear similar, do not assume a valid Bitcoin format result means the address is a valid Litecoin address.
What should I do before sending cryptocurrency to an address?
Always validate the format first. Then send a small test transaction to confirm receipt before sending the full amount. Double-check the network, an Ethereum address on the wrong network (e.g. sending ERC-20 tokens to the Binance Smart Chain instead of Ethereum mainnet) can result in permanent loss of funds. Cryptocurrency transactions are irreversible.
Also known as
Bitcoin address validatorEthereum address checkcrypto wallet validatorvalidate BTC addressETH address validator