Buy & Swap Siacoin (SC)

What Sia says it is

Sia's homepage calls it "the world's safest cloud storage, by design". The documentation gives a plainer definition: Sia is decentralised, peer-to-peer cloud storage with no central provider and no gatekeepers, where files are encrypted on your own device before upload so that no storage provider can read them, and you hold the keys. The network is developed by a non-profit and runs on open-source software.

The about page frames the mission as protecting people's data and enabling privacy-preserving applications. It sets out a case against traditional storage — data held in one place by a single company, blind trust, limited competition, the possibility of data being sold or used to train AI, and the power to take files down — and positions Sia as the alternative.^{[1], [2], [3]}

How it works

According to the homepage, Sia stores but never sees your data. Each file is split into small encrypted shards, which are shuffled and distributed across the decentralised network of hosts. Because pieces are spread across many machines, the site says retrieval can happen in parallel, making the system faster and more resilient to outages. The project recently published work on its own Reed-Solomon erasure-coding library, the technique that lets a file be rebuilt even if some hosts go offline.

The documentation describes different software for different roles. Everyday users can start with the Sia Storage app for iOS and Android, which offers a free 50 GB account. More technical users can run renterd or indexd to store data, hostd to provide storage and earn Siacoin, and walletd to hold and manage Siacoin. Developers can build on Sia through a developer portal and SDK, and S3-compatible integrations exist.

Sia's history is long by crypto standards. The about page says it was conceived at HackMIT in 2013 by Luke Champine and David Vorick, launched mainnet in 2015, reached one petabyte stored at a single time in 2018, created the Sia Foundation in 2020, and in 2025 shipped a major V2 overhaul of its software and protocol.^{[4], [5], [6], [7], [8]}

What Siacoin is used for

Siacoin is the payment currency that links the two sides of the market. The docs direct anyone who wants to "provide storage and earn Siacoin" to set up hostd: hosts are paid in SC for storing other people's data. Users who store data pay for that capacity, and the walletd software exists specifically to hold and transfer Siacoin.

The Sia Foundation describes itself as a non-profit sustained by community donations, and the homepage reports grant funding allocated to projects built on the network. The docs also include a page on Siacoin's total supply, and the site links to MiCA indicators and a guide for exchanges wishing to list Siacoin.^{[9], [10], [11], [12]}

Risks and open questions

Decentralised storage shifts responsibility to the user. Because files are encrypted on your device and you hold the keys, losing your seed phrase means losing access — there is no provider who can reset it. The docs devote a page to the importance of the Sia seed for this reason.

Host reliability varies, which is why Sia relies on redundancy across many hosts, and why community tools such as HostScore exist to benchmark them. The about page's claim that Sia has never had downtime is the project's own statement. As with any network upgrade, the V2 hardfork required users and hosts to update software.^{[13], [14], [15]}

What the official sources do not say

UNKNOWN from official sources: the pages reviewed do not state the current total data stored on the network, typical storage prices in Siacoin, or how the free 50 GB tier in the Sia Storage app is funded over the long term.

Nothing here predicts the coin's future price or adoption.