<p>Those are invalid addresses that don't belong to any cryptocurrency. You should file a bug report at <a href="https://github.com/Blockchair/Blockchair.Support/issues" rel="nofollow noreferrer">https://github.com/Blockchair/Blockchair.Support/issues</a> since those might even be their database secrets.</p>
<p>Those are of 16 bytes. My initial guess about their format would be SHA-1, but Bitcoin does not use SHA-1. Probably it's related to their database.</p>
<p>For example on this page <a href="https://blockchair.com/dogecoin/address/942943e227462513f33c4f32ec6f1e56" rel="nofollow noreferrer">https://blockchair.com/dogecoin/address/942943e227462513f33c4f32ec6f1e56</a> it seems Blockchair thinks <code>942943e227462513f33c4f32ec6f1e56</code> is a valid Doge address. It's not.</p>
<p>To prevent this from happening again in the future, they could implement input sanitization before INSERT statements</p>

CC BY-SA 4.0
2020-07-02T09:29:09.130Z
Thank you. I've raised an issue on their support forum: https://github.com/Blockchair/Blockchair.Support/issues/273
Martin
CC BY-SA 4.0
2020-07-10T11:53:58.103Z
I've received a response from Blockchair support and provided the outcome in a separate answer. Thank you again for your input, which ultimately led to me finding the answer!
Martin
CC BY-SA 4.0
2020-07-02T09:02:07.443Z
2020-07-02T09:02:07.443Z
MCCCS
<p>Having investigated this following @MCCCS's <a href="https://bitcoin.stackexchange.com/a/96780/106912">answer</a>, the following is information about the addresses provided by Blockchair support in response to the <a href="https://github.com/Blockchair/Blockchair.Support/issues/273" rel="nofollow noreferrer">issue I raised in their GitHub</a>:</p>
<blockquote>
<p>In fact, there are no addresses on the Bitcoin blockchain. There are
only scripts, some of them are standard and can be converted to a
Bitcoin address, some of them can’t — like nulldata (OP_RETURN)
outputs, nonstandard, and bare multisig. We use the d- prefix for
nulldata, m- for bare multisig, and s- for everything else.</p>
<p>This is briefly mentioned in this API documentation section:
<a href="https://blockchair.com/api/docs#link_300" rel="nofollow noreferrer">https://blockchair.com/api/docs#link_300</a></p>
</blockquote>
<p>Therefore, these <em>addresses</em> (for want of a better word) are valid transactions on the Bitcoin blockchain.</p>
<p>The prefixes used are:</p>
<ul>
<li><code>d-</code> nulldata</li>
<li><code>m-</code> bare multisig</li>
<li><code>s-</code> everything else</li>
</ul>
<p>In conclusion, the <strong>data is valid</strong> but the outputs are not addresses in the normal sense of the word.</p>

CC BY-SA 4.0
2020-07-10T11:53:13.503Z
2023-12-11T16:48:55.550Z
2023-12-11T16:48:55.550Z
Martin
<p>I've obtained a list of all current Bitcoin addresses with balances from Blockchair, which is downloadable from their data repository located <a href="https://blockchair.com/dumps" rel="nofollow noreferrer">here</a>.  I have downloaded the <code>Bitcoin / Addresses</code> TSV database dump.</p>
<p>The list consists of:</p>
<ul>
<li>~23m P2PKH (<code>1xxx</code>) addresses</li>
<li>~5.8m P2SH (<code>3xxx</code>) addresses</li>
<li>~1.3m Bech32 (<code>bc1xxx</code>) addresses</li>
</ul>
<p>However, there are also ~400k addresses that have prefixes that I don't recognise, including:</p>
<ul>
<li>d-xxx (example: <code>d-b697921d996831d1a26ca8d8e92571c1</code>)</li>
<li>m-xxx (example: <code>m-942943e227462513f33c4f32ec6f1e56</code>)</li>
<li>s-xxx (example: <code>s-2ad548f2459c0ed6123400e5d61a479e</code>)</li>
</ul>
<p><strong>Are these valid Bitcoin addresses?</strong></p>
<p>If they are, how do I view information about them?</p>
<p>If they are not, any idea why they appear in the dump of current Bitcoin addresses from Blockchair?</p>

<address><address-generation>
Unknown Address Format Parsing Bitcoin Addresses from Blockchair Data
Martin
# Unknown Address Format Parsing Bitcoin Addresses from Blockchair Data

(Asked by: username_0 on 2020-07-02)

I've obtained a list of all current Bitcoin addresses with balances from Blockchair, which is downloadable from their data repository located [here](https://blockchair.com/dumps). I have downloaded the `Bitcoin / Addresses` TSV database dump.

The list consists of:

* ~23m P2PKH (`1xxx`) addresses
* ~5.8m P2SH (`3xxx`) addresses
* ~1.3m Bech32 (`bc1xxx`) addresses

However, there are also ~400k addresses that have prefixes that I don't recognise, including:

* d-xxx (example: `d-b697921d996831d1a26ca8d8e92571c1`)
* m-xxx (example: `m-942943e227462513f33c4f32ec6f1e56`)
* s-xxx (example: `s-2ad548f2459c0ed6123400e5d61a479e`)

**Are these valid Bitcoin addresses?**

If they are, how do I view information about them?

If they are not, any idea why they appear in the dump of current Bitcoin addresses from Blockchair?

**Tags:** address, address-generation


---

## 2 answers

### Answer by username_0 on 2020-07-10. Score: 7 | Accepted answer

Having investigated this following @username_1's [answer](https://bitcoin.stackexchange.com/a/96780/106912), the following is information about the addresses provided by Blockchair support in response to the [issue I raised in their GitHub](https://github.com/Blockchair/Blockchair.Support/issues/273):

> In fact, there are no addresses on the Bitcoin blockchain. There are
> only scripts, some of them are standard and can be converted to a
> Bitcoin address, some of them can’t — like nulldata (OP\_RETURN)
> outputs, nonstandard, and bare multisig. We use the d- prefix for
> nulldata, m- for bare multisig, and s- for everything else.
>
> This is briefly mentioned in this API documentation section:
> <https://blockchair.com/api/docs#link_300>

Therefore, these *addresses* (for want of a better word) are valid transactions on the Bitcoin blockchain.

The prefixes used are:

* `d-` nulldata
* `m-` bare multisig
* `s-` everything else

In conclusion, the **data is valid** but the outputs are not addresses in the normal sense of the word.


---

### Answer by username_1 on 2020-07-02. Score: 2

Those are invalid addresses that don't belong to any cryptocurrency. You should file a bug report at <https://github.com/Blockchair/Blockchair.Support/issues> since those might even be their database secrets.

Those are of 16 bytes. My initial guess about their format would be SHA-1, but Bitcoin does not use SHA-1. Probably it's related to their database.

For example on this page <https://blockchair.com/dogecoin/address/942943e227462513f33c4f32ec6f1e56> it seems Blockchair thinks `942943e227462513f33c4f32ec6f1e56` is a valid Doge address. It's not.

To prevent this from happening again in the future, they could implement input sanitization before INSERT statements

> **Comments:**
> **username_0**: Thank you. I've raised an issue on their support forum: https://github.com/Blockchair/Blockchair.Support/issues/273  
> **username_0**: I've received a response from Blockchair support and provided the outcome in a separate answer. Thank you again for your input, which ultimately led to me finding the answer!  

---

