Bitcoin and Ethereum Address Validator

How to Check a Bitcoin or Ethereum Address

Checking an address takes a few seconds. Paste the address into the field at the top of the page and click “Check Address”. The tool immediately shows whether the format is supported, which network it recognized, and whether the checksum matches.

The field is prefilled with the sample Bitcoin address bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4, and validation starts automatically when the page loads. For this example, the result is: Network Bitcoin; Encoding bech32; Checksum ✓ valid (SegWit v0).

1. Copy the address from your wallet, an exchange, or the message where you received it.
2. Paste it into the address field and click “Check Address.”
3. Read the result and pay attention to the recognized network and the checksum information.

Everything runs locally in your browser, so the address you enter is never sent anywhere.

Bitcoin Address Formats: Base58Check, Bech32, and Bech32m

Bitcoin uses several address encodings. The validator recognizes them by their starting characters and length and shows which format it is dealing with.

Base58Check is the oldest encoding. On Bitcoin mainnet, these addresses start with 1 or 3, and their checksum is calculated differently than in Bech32.

Bech32 is written in lowercase and starts with bc1. Version 0 of this encoding corresponds to SegWit v0 addresses, such as the popular addresses beginning with bc1q.

Bech32m is a newer variant of the same encoding, used for version 1 and higher. Version 1 is Taproot addresses. The tool recognizes the address version and selects the correct checksum calculation for it.

Testnet addresses follow the same rules, but with the tb1 prefix.

EIP-55 Checksums in Ethereum

An Ethereum address, as well as addresses on other EVM-compatible networks, is 40 hexadecimal characters preceded by 0x. The characters alone are not enough to catch a typo, which is why EIP-55 was introduced.

It works by capitalizing some letters in the address. Which letters are uppercase is determined by a checksum calculated from the address itself. This lets a wallet or validator detect an accidental reordering or replacement of a character.

How the tool interprets letter case:

• If the address is all lowercase or all uppercase, you will see the result “no checksum”. Such an address is formally valid, but it does not include EIP-55 protection.
• If the address has both lowercase and uppercase letters, the tool compares it with the EIP-55 checksum and shows ✓ or ✗. It also displays the address in the correct checksummed form, ready to copy.

Keep in mind that a checksum protects against typos, not fraud. An address can pass validation and still belong to someone other than the person you expect.

Testnet and Mainnet Addresses — What They Mean

The address itself sometimes reveals which network it belongs to. In Bitcoin, the prefixes 1 and 3 and bc1 indicate mainnet, while m, n, 2, and tb1 indicate testnet. The tool shows the recognized network, so you can immediately see whether you are looking at a mainnet or testnet address.

Testnet is for practice and application testing. Testnet addresses look similar to regular ones, but they operate in a separate environment and should not be used for ordinary transfers.

Ethereum is different: the same address format applies on mainnet, testnets, and layer-2 networks. The validator can therefore only confirm that the format is valid — it will not tell you which network the address exists on. Before sending funds, make sure in your wallet that the selected network matches the recipient’s address.

Validator Limitations — What It Does Not Check

The tool checks the address format and its checksum. It does not answer whether the address exists, who controls it, or whether it is safe.

• It does not check balance or transaction history.
• It does not confirm that the address belongs to the right person or is not linked to fraud.
• It does not recognize formats beyond those described above — in that case, it displays a message that the format was not recognized.
• In Ethereum, it does not distinguish mainnet from testnets or layer-2 networks, because the address format is identical.
• It is not a substitute for checking in a wallet, which often also verifies the network and supported address standard.

Treat the result as a quick first-step check. If an address passes validation, that is good, but before sending funds you should still compare it with the recipient’s address character by character.

Frequently Asked Questions

The tool only checks whether the address is formatted correctly and its checksum is valid; it does not confirm the owner of the address or guarantee that the address is currently in use — before sending funds, verify the address in a trusted wallet.