Permanent data

Permanent data

Permanence guarantees your data can be retrieved at any point in the future.

Permanent data is fault-tolerant, tamperproof, and paid-for:

  • Fault-tolerant

    Data is stored so that it can survive unexpected events, including data corruption and loss.

  • Tamperproof

    Stored data is immutable, it can’t be maliciously changed.

  • Paid-for

    The cost of storing the data permanently is covered up-front, and there is a mechanism for paying miners on an acceptable cadence.


Your data is replicated across multiple Arweave nodes. Current estimates (opens in a new tab) show there are 781+ complete replicas of the data, ensuring that no number of failed drives or natural disasters can damage your data.


Your data is identifiable by a unique identifier formed by hashing the upload. Every piece of data produces a distinct hash, even a minute change in the original content results in a completely different identifier. This makes it easy to verify and ensure that the stored data remains unaltered over time.


When you upload data you pay a single up-front fee. The upload fee is divided, 5% is paid to the miner who includes your transaction in a winning block, and 95% is reserved for future funding of storage via the Arweave endowment.

The Arweave endowment uses the current cost of storage combined with a conservative estimate of how much storage costs decline year on year to ensure there are always enough funds available to pay miners for continued storage. Arweave has published simulations (opens in a new tab) showing how the current endowment will last at least 10,000 years.

How will this evolve?

The Arweave endowment is based on current storage technology, their current cost and declining costs over time. The Arweave yellow-paper (opens in a new tab) acknowledges that the most important thing is data permanence, not network permanence (opens in a new tab) and at some point in the future when "a permanent information storage system more suited to the challenges of the time emerges, the Arweave’s data will be ‘subsumed’ into this network."

Why does permanent data matter?

Permanence ensures the security of all data posted to Irys. No hostile party, not even a government, can alter this.

It also enables composability. Chunks of permanent data can be used as primitives to power the next iteration of the internet, the permaweb.

Irys enables a global dataset that will always be reliable and accessible.

Getting started

You can permanently upload data in 3 lines of code.

// Connect and fund
const irys = new Irys({ network, token, key });
const fundTx = await irys.fund(irys.utils.toAtomic(0.05));
// Upload data
const receipt = await irys.uploadFile("./myImage.png");

For full code examples, you can copy and paste into your projects, check out our SDK.

If you are building a browser-based app, check out Irys in the browser, and the Provenance Toolkit, a suite of UI open-source UI components for managing node balances and uploading files.

Our query package contains everything you need to search Irys transaction metadata.

Beginners should start with our SDK tutorial.

What can you build with permanent data?

Learn more in our use-cases section (opens in a new tab).