btcmessage.com

What It Is

BTCMessage is an experimental developer tool for Bitcoin users, designed to “send a message to any Bitcoin address.” It is not a chat system. Instead, it generates a set of transaction outputs: each line of the message is displayed as a manually constructed vanity Bitcoin address, and the user then copies these outputs into a wallet such as Electrum to send the transaction. Once sent, the message can be viewed in a block explorer.

Core Capabilities and Technical Implementation

The tool’s main use case is figuring out how to draw the attention of a party associated with a Bitcoin address when no communication channel has been established. Examples on the page include contacting an address that received funds by mistake, adding a note to a donation, or leaving a suggestion for a particular address. It works by creating Base58 addresses that pass the checksum and embedding text into the address characters. It then uses BIP0069 output ordering rules and incrementally increases output amounts so the message is displayed in the correct order. The page also offers configuration options such as padding character, character group size, additional send amount, and whether to use the 1BTCmsg header.

Pricing and Costs

The site does not state that the tool itself is paid, but on-chain costs should not be ignored. By default, each message output is 0.00000546 BTC, the minimum output amount, and users also need to pay Bitcoin transaction fees. The optional 1BTCmsg header address belongs to the author, who notes that they may receive a small amount of BTC from each message. As a result, it is not suitable for high-frequency communication or long-form text.

Pros and Cons

Its advantages are that the mechanism is straightforward, the result can be verified in a block explorer, and the page explains concepts such as checksum, SHA256, and BIP0069 relatively clearly. The downsides are also obvious: messages are completely public, the outputs are effectively burned, and they create unspendable UTXOs that add burden to the network state. Users also need to manually copy and verify addresses and amounts, which introduces operational risk. The page itself recommends using alternatives such as OP_RETURN first to avoid creating unnecessary burden for node operators.

Who It’s For and Access from China

BTCMessage is better suited to Bitcoin developers, on-chain investigators, or a very small number of users who need to publicly contact a specific address. It is not suitable for ordinary communication, marketing, or frequent use. The original page does not provide information about access from mainland China, so availability is unknown. On the payment side, it depends on BTC and on-chain transaction fees. Alternatives include OP_RETURN, wallets that support custom transaction construction, or scripting tools.