bitsms

bitsms.org

Send Bitcoin offline via SMS

Text a signed raw transaction to this number. Created for Orum Wallet.

Bitsms increases the accessibility of Bitcoin, allowing it to be used in places with cellular infrastructure but no Internet infrastructure. It also allows for sending Bitcoin on a cellular plan without data.

Example

0100000001f3f6a909f8521adb57d898d2985834e632374e770fd9e2b98656f1bf1fdfd427010000006b48304502203a776322ebf8eb8b58cc6ced4f2574f4c73aa664edce0b0022690f2f6f47c521022100b82353305988cb0ebd443089a173ceec93fe4dbfe98d74419ecc84a6a698e31d012103c5c1bc61f60ce3d6223a63cedbece03b12ef9f0068f2f3c4a7e7f06c523c3664ffffffff0260e31600000000001976a914977ae6e32349b99b72196cb62b5ef37329ed81b488ac063d1000000000001976a914f76bc4190f3d8e2315e5c11c59cfc8be9df747e388ac00000000

b138360800cdc72248c3ca8dfd06de85913d1aac7f41b4fa54eb1f5a4a379081

Once the transaction is sent successfuly, Bitsms replies with the transaction ID. If the same transaction has already been sent or contains errors, Bitsms will not reply.

How it works

Bitsms is not a wallet. Instead, it is an SMS to Bitcoin relay where you sign a transaction in your wallet and text it to this number. Most wallets allow you to sign raw transactions offline.

Bitsms is open source and available on Github.

Create a signed raw transaction

Here are instructions on signing a raw transaction for various wallets:

Split a transaction

This is an upcoming feature that allows you to send transactions, even if you can't text SMS messages larger than 160 or 67 characters. This works by splitting the transactions into separate parts.

Save this page offline

It is recommended that you download this page to use it offline. On desktops this can be done by going to File > Save. ⌘S is the macOS keyboard shortcut while Ctrl+S is the Linux/Windows shortcut. Here are instructions for saving a page offline on a mobile device:

Developer guide

Read the developer guide for steps on running a Bitsms instance and integrating it with your apps.