Storage prices on the Sia network are measured in Siacoins (SC), the cryptocurrency used to buy and sell storage on the network. The price of one Siacoin is valued in both USD and Bitcoin (BTC), and is subject to change a little bit each day like other cryptocurrencies. Occasionally, the price of a Siacoin may change significantly, especially over a long period of time. The coin price shown here is the average price of Siacoins right now across several different cryptocurrency exchanges.
Storage on the Sia network is usually priced around the equivalent of $2 USD per Terabyte per Month. With a current Siacoin price of $0.02 USD, you could expect to spend about 100 SC a month for each terabyte you wanted to rent ($2.00 / $0.02 = 100 SC).
Hosts that sell their storage on the Sia network set their own pricing individually. When you rent storage on Sia, you'll be interacting with several hosts, so Sia will automatically pick the hosts that it finds most competitive based on a number of factors, including price. For this reason, all pricing information is only a rough estimate based on network averages.
In addition to the basic cost of renting storage, there are a few other fees that you'll be subject to paying as a renter. These vary from host to host, as hosts set their own prices individually, but on average:
- Contract Fees - When you send Siacoins (i.e. pay your host) or create storage contracts on the blockchain, it costs a very small amount to do so. Contract fees help cover these transaction fees. Contract fees are a one-time fee per contract and are usually between 2-5 SC.
- Bandwidth Fees - Hosts can set pricing for both upload and download bandwidth to their server. If you plan on frequently uploading or downloading new data, these fees may stack up. Fees for upload and download bandwidth have recently been averaging around 25 SC per TB.
- SiaFund Fees - the long-term development of Sia is funded by something called a SiaFund, which collects revenue from a small (~3.9%) fee on the collateral a host puts up. This fee is usually paid by the renter, and is usually somewhere around 10 SC per TB.
You can get a more exact idea of the cost of renting on Sia based on your specific renting requirements using our Renting Calculator.
When you rent storage on Sia, the contract length is set to about 3 months by default. Therefore, when you upload files, you will be charged for 3 months worth of storage at that time. Budget accordingly! For example, if storage is about 50 SC/TB/Month and you plan on utilizing a full terabyte, plan to allocate at least 150 SC for the cost of storage over 3 months.
Once you set an allowance (explained below), Sia will start to find hosts and form contracts with them. Sia currently picks hosts automatically based on a number of Host Scoring metrics, which take things like storage prices and host uptime into account. Sia will form contracts with 50 hosts by default, distribute your data to 30 of them, and find new hosts automatically if any of your existing hosts go offline or lose your data. Sia will also sometimes create more than 50 contracts if it finds new hosts that are more competitive (in terms of the Host Scoring metrics) than your current hosts.
When you rent storage on Sia, you control how much storage space you use by setting a Siacoin allowance. Your allowance is basically a budget that caps your spending at or below that amount. You can set your allowance to whatever you'd like, and you can change your allowance at any time. However:
- If you set your allowance too low, you may not be able to upload (or download) all of your data. If your allowance is set extremely low, you won't be able to form enough contracts to upload anything in the first place.
- If you set your allowance very high, you might accidentally spend more Siacoins than you'd planned on if you frequently upload or download data. A high allowance also puts you at risk of spending more Siacoins than you want in the event Sia excessively creates new contracts with hosts it thinks are more competitive, or if Sia picks expensive hosts.
In any event, you'll only be charged for the storage and bandwidth that you actually use, because you're charged for the storage of each file at the time you first upload it. Trying to set your allowance close to what you actually expect to spend is the best policy, and you can adjust it later if needed.
When you set an allowance, contracts start to form immediately. Sia locks up your allowance amount for the duration of the storage contract, so you'll see it start to be taken out of your wallet immediately. This will appear as several small transactions in your wallet, as Sia creates contracts with hosts and locks up Siacoins in an allocation to each host. If you don't upload enough data to completely use your allowance, the amount that you didn't spend will be returned to you at the end of the contract. In other words, whatever you set your allowance to, that amount will mostly be inaccessible to you until the contract is over, even if you don't spend all of it.
You can get a recommendation on a starting allowance based on your specific renting requirements using our Renting Calculator.
Notice: Sia is still in development. While rare, various renting issues have been reported that sometimes result in excessive spending of Siacoins, inability to recover data, or both. It is not currently recommended to store critical data on Sia without having another backup elsewhere.
Warning: Sia currently relies on local metadata stored on your renter machine to retrieve files. This means that you cannot simply upload files to the Sia network and then retrieve them again from any computer, or retrieve them if your computer crashes, without also having a backup of the metadata. Additionally, metadata backups must be current - if you back up the metadata and then upload or download a file, you need to back up the metadata again. See this FAQ topic for the location of this metadata. We recommend Sia for cold storage use only until this limitation is removed.
Uploading data via the Sia-UI is very easy - you simply select files or folders to upload, and they'll be on their way. Upload speeds will vary based on your internet connection and your hosts' internet connections, but typically run about 3 MB/second in our testing of uploads over a gigabit connection on our end.
As mentioned above, you're only charged for the storage that you use, and you're only charged as you use it. For that reason, you can upload as much data as you'd like, up until your allowance runs out. You can increase your allowance to continue uploading if this happens.
40 MB Atomic Filesize
Sia currently has a limitation of a 40 MB atomic filesize, which means that this is the smallest file that Sia can support. You can upload smaller files, but they'll be treated as if they're 40 MB and padded to that size. If you upload 20 music files at about 5 MB each, they won't take up 100 MB on Sia, they'll take up 800 MB! For this reason, it's suggested that you zip smaller files together. You'll save a lot of Siacoin, especially if almost all of your files are small. There are plans to reduce the atomic filesize to closer to 100 KB, but this has not yet been implemented.
As you've probably read by now, Sia splits your files across 30 hosts for 3x redundancy, and only 10 pieces of a file are needed to reconstruct it. For that reason, you should wait to upload any files until Sia says that you have at least 30 contracts. When you upload files, they'll get to about 2x redundancy, and then show Boosting Redundancy in the File Transfer tab until they reach 3x redundancy. If your files drop below 3x redundancy, they'll be boosted again the next time you open Sia. Wait until any files with red or yellow "block" icons turn to green blocks, and then you're good to go.
Retrieving files is about as easy as uploading them - simply click on your file(s) in the Files section, and click the Download button that appears at the bottom of the window (the first button that looks like a cloud with a down arrow). You can download multiple files at once, though sometimes this will cause errors - try one file at a time if so.
You'll need some of your Siacoin allowance available to download your files again, because hosts also charge for download bandwidth. If your allowance is completely spent, you won't be able to recover your files, so keep that in mind.
There are three important housekeeping items that Sia needs to perform when you're renting storage on the Sia network:
- Refreshing your allowance - About six weeks after your contracts are created, your allowance attempts to refill itself. The assumption is that after 6 weeks, contracts have been created and data has been uploaded, so your allowance is topped off in order to facilitate contract renewals and downloads through the rest of the contract period.
- Renewing your contracts - Your storage contracts will renew automatically at the end of the contract period. By default, Sia will attempt to renew your contract within about 3 weeks of the contract expiration date. If you started renting at the beginning of May, your 3 month contracts would expire around the end of July. Sia would attempt to renew them after about the first week of July.
- Boosting file redundancy - File redundancy is also boosted if needed, as described in the section above.
Sia needs to be running with your wallet unlocked for these things to occur, so as a renter, it's a good idea to open Sia at least once a month and let it run overnight to take care of miscellaneous housekeeping tasks such as these. If you simply upload files and then never open Sia again, your allowance and your contracts will eventually expire and your files will be immediately deleted once your contracts are no longer valid!