<blockquote>
  <p>Can I send almost 1MB transaction?</p>
</blockquote>

<p>To be able to send a transaction that a miner will accept, that transaction has to be a standard transaction. As defined in <a href="https://github.com/bitcoin/bitcoin/blob/eb7daf4/src/policy/policy.h#L24" rel="noreferrer"><code>policy.h</code></a></p>

<pre><code>/** The maximum weight for transactions we're willing to relay/mine */
static const unsigned int MAX_STANDARD_TX_WEIGHT = 400000;
</code></pre>

<p>For non-Segwit transactions, the limit is <code>400,000 KB / 4 = 100,000 B = 100 kB</code>.</p>

<p>Therefore, if you have a Pre-Segwit transaction larger than 100 kB but smaller than the block s̶i̶z̶e weight limit, you should contact a miner, and they'll be able to add your transaction to their block manually, if it's profitable for them.</p>

CC BY-SA 4.0
2019-03-05T14:33:54.770Z
So 100kB limit still persists, I was confused by the comment to https://bitcoin.stackexchange.com/a/35882/92719 . Thanks a lot
Lizzy Bug
CC BY-SA 4.0
2019-03-05T14:36:36.687Z
You're welcome. If you have any other questions, I'm happy to help.
MCCCS
CC BY-SA 4.0
2019-03-05T13:43:37.953Z
2019-03-05T13:43:37.953Z
MCCCS
<p>Block size is still limited to 1MB. As I understood, transaction size is no longer limited. So can I be sure that my transaction with 29000 outputs and reliable fee will be included into block?
Or what is the max transaction size?</p>

CC BY-SA 4.0
2019-03-05T13:42:25.793Z
Yes, but the question and both answers are not relevant now
Lizzy Bug
CC BY-SA 4.0
2019-03-05T21:16:40.947Z
Related: Block 364292 is basically one massive transaction: https://blockstream.info/block/000000000000000003dd2fdbb484d6d9c349d644d8bbb3cbfa5e67f639a465fe
chytrik
<transactions><json-rpc><raw-transaction><full-node>
Can I send almost 1MB transaction?
Lizzy Bug
# Can I send almost 1MB transaction?

(Asked by: username_0 on 2019-03-05)

Block size is still limited to 1MB. As I understood, transaction size is no longer limited. So can I be sure that my transaction with 29000 outputs and reliable fee will be included into block?
Or what is the max transaction size?

**Tags:** transactions, json-rpc, raw-transaction, full-node

> **Comments:**
> **username_0**: Yes, but the question and both answers are not relevant now  
> **username_1**: Related: Block 364292 is basically one massive transaction: https://blockstream.info/block/000000000000000003dd2fdbb484d6d9c349d644d8bbb3cbfa5e67f639a465fe  

---

## 1 answers

### Answer by username_2 on 2019-03-05. Score: 6 | Accepted answer

Can I send almost 1MB transaction?

To be able to send a transaction that a miner will accept, that transaction has to be a standard transaction. As defined in policy.h
/** The maximum weight for transactions we're willing to relay/mine */
static const unsigned int MAX_STANDARD_TX_WEIGHT = 400000;

For non-Segwit transactions, the limit is 400,000 KB / 4 = 100,000 B = 100 kB.
Therefore, if you have a Pre-Segwit transaction larger than 100 kB but smaller than the block s̶i̶z̶e weight limit, you should contact a miner, and they'll be able to add your transaction to their block manually, if it's profitable for them.

> **Comments:**
> **username_0**: So 100kB limit still persists, I was confused by the comment to https://bitcoin.stackexchange.com/a/35882/92719 . Thanks a lot  
> **username_2**: You're welcome. If you have any other questions, I'm happy to help.  

---

