user3029: I have a bitcoin address and I want to get the JSON format of the balance using blockstreams api service. 
It's this one: https://github.com/Blockstream/esplora/blob/master/API.md#transaction-format
It's not clear on what I need to put in the URL. I tried: 

https://blockstream.info/address/:bc1xxxxxxx

and it doesn't work. 

user14871: As others have said you can use https://blockstream.info/api/address/bc1qgsmfaz22lzy08wqjspd8xtm43hal5tgz4hyac6 for the JSON - the doc is in reference to running a local instance - the exact endpoint is depending on deployment, the default deployment we use has nginx forward /api/ requests to electrs without the api bit https://github.com/Blockstream/esplora/blob/master/contrib/nginx.conf.in#L32 but it depends on how people want to deploy it.
We should probably mention this in the API.md file to avoid confusion

3029: <p>I have a bitcoin address and I want to get the JSON format of the balance using blockstreams api service. </p>

<p>It's this one: <a href="https://github.com/Blockstream/esplora/blob/master/API.md#transaction-format" rel="nofollow noreferrer">https://github.com/Blockstream/esplora/blob/master/API.md#transaction-format</a></p>

<p>It's not clear on what I need to put in the URL. I tried: </p>

<blockquote>
  <p><a href="https://blockstream.info/address/:bc1xxxxxxx" rel="nofollow noreferrer">https://blockstream.info/address/:bc1xxxxxxx</a></p>
</blockquote>

<p>and it doesn't work. </p>
 14871: <p>As others have said you can use <code>https://blockstream.info/api/address/bc1qgsmfaz22lzy08wqjspd8xtm43hal5tgz4hyac6</code> for the JSON - the doc is in reference to running a local instance - the exact endpoint is depending on deployment, the default deployment we use has nginx forward <code>/api/</code> requests to electrs without the <code>api</code> bit <a href="https://github.com/Blockstream/esplora/blob/master/contrib/nginx.conf.in#L32" rel="noreferrer">https://github.com/Blockstream/esplora/blob/master/contrib/nginx.conf.in#L32</a> but it depends on how people want to deploy it.</p>

<p>We should probably mention this in the API.md file to avoid confusion</p>
