What is cardano's block size limit?

What is cardano’s block size limit? Cannot find the answer anywhere.

2MBs. There is also a 8kb transaction size limit.


This is going to be a weird follow up question but is it possible to show an example of a 8kb transaction or amount of code in how it looks, somewhat as a reference of how concise a transaction would have to look like? Is this the limitation of what a smart contract would have to be coded as?

My only reference is doing some VBA in excel so I don’t know how the code would look regarding an ADA transaction. I am only imagining if there could be smart contracts that have a complicated series of conditions that could get lengthy and difficult to keep concise.

Even if anybody has a html file or something in a parallel language that shows what 8kb looks like.

Think of a transaction with many many inputs (utxo) for example because the wallet has lots of dust. To prevent this happening its very important that the wallets pick utxo clever. 8KB would be still huge.

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I’m wondering about this too, do contract scripts (the on-chain part, of course) have to fit within transactions or do they “live” somewhere else?

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in 2018 there was some transactions who had included some extra data, (eg encoded image, secret message, …) If you search the forum for “extra long addresses” you can see some examples.
May also look at this script https://github.com/sdlck/cardano-utils/tree/master/address-data-embedder

Then the 8KB TX size limit was introduced.

For thus who wonder why only 2MB.
keep in mind this is 2MB per slot = 20 seconds.
Considering the average TX size on the Cardano mainnet is around 500 Bytes, this would mean 4096 transactions per slot, or 205 per second.


Slot is 1 second. Block is about 20s. U probably made a bit mess here.

This is from 2018 in the federated network setting. After the shelley hardfork (August 2020) we are now with 1sec slots and a 5% density resulting in an average block time of 20seconds.

hi bro, I’m newbie here, I have heard that now they just increase the block size to 72KB, so they can still increase block size in the future but the maximum block size that is possible on the protocal is 2MB (approximately 27.7 times bigger than the current 72KB), am I understand correctly?

No, the answer in this thread is no longer relevant. The Shelley hardfork in 2020 changed how all the parameters work


could you pls tell me what is the block size maximum limit?

88KB: https://twitter.com/InputOutputHK/status/1518596128056520707

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