If you have ever opened your wallet's network settings and seen a field called "RPC URL" sitting next to the chain ID, you have run into a part of how wallets work that most people never think about. It sounds technical, but the idea behind it is simple, and understanding it clears up a few things that otherwise feel mysterious, like why a balance sometimes looks out of date or why adding a network by hand asks for a strange web address.
The problem an RPC endpoint solves
Base, like other blockchain networks, is not a single computer somewhere that your wallet dials into. It is a large, distributed network of nodes, each one keeping a full copy of the chain's history and processing new transactions as they arrive. Your phone or laptop does not run one of these nodes itself. Running a full node takes significant storage and bandwidth, far more than makes sense for an app you check a few times a day.
So your wallet needs a way to ask questions of the network without hosting a copy of it. Questions like: what is this address's ETH balance, has this transaction confirmed yet, what is the current gas price. That is what an RPC endpoint is for. RPC stands for "remote procedure call," which is a general computing term for asking a different machine to run something on your behalf and hand back the result. An RPC endpoint is simply a web address that a node operator makes available, so that wallets and apps can send it these questions and get real answers straight from the chain.
What actually happens when you use your wallet
Every time your wallet shows you a token balance, submits a swap, or waits for a confirmation, it is quietly sending a request to an RPC endpoint behind the scenes. The endpoint forwards that request to an actual Base node, gets the current, correct answer, and sends it back. This happens constantly and invisibly. You are never meant to notice it, in the same way you are not meant to notice your browser making dozens of requests to load a single webpage.
For Base specifically, there is a public endpoint anyone can use, https://mainnet.base.org, maintained as part of the Base project itself. Most wallets have this, or an equivalent from a node provider, built in by default under Base's chain ID, which is 8453. That is why adding Base to a wallet is usually a one-click "add network" button rather than something you configure by hand. The wallet already knows which RPC endpoint to talk to.
Why you sometimes have to enter one manually
Occasionally a wallet does not have a network pre-configured, or you are using one that supports custom networks generally rather than shipping with Base built in. In that case, you may be asked to fill in a few fields yourself: a network name, the chain ID, a currency symbol, and the RPC URL. This is where people sometimes get nervous, because it looks like a technical setting that could be gotten wrong.
The good news is that getting it wrong is rarely dangerous, just inconvenient. If the RPC URL is incorrect or offline, your wallet simply will not be able to fetch data or send transactions on that network. It will not connect, and nothing will happen until you fix it. The chain ID is the part worth double-checking carefully, since it is what tells your wallet, and any app you connect to, which network you actually mean. Base mainnet's chain ID is 8453. If you ever add a network manually, cross-checking the chain ID and RPC URL against Base's own documentation rather than a random search result is the safer habit.
Why a stale balance is sometimes an RPC issue, not a wallet issue
If a balance looks frozen, a transaction seems to vanish, or a page that reads on-chain data will not load, the RPC endpoint your wallet or the app is using is a common, boring explanation. Public RPC endpoints are shared by a lot of traffic and rate limited, so during busy periods they can respond slowly or time out. This is not the same thing as your funds being at risk. Your balance and transaction history live on the Base network itself, not inside any particular RPC endpoint. A slow or unresponsive endpoint just means the messenger is having a rough moment. The information it is trying to fetch is unaffected, and a refresh, a short wait, or switching to a different RPC endpoint will usually clear it up.
This is also why larger apps and services generally do not rely on the free public endpoint for everything. Dedicated node providers exist specifically to offer faster, more reliable RPC access for apps that need to handle a lot of requests, which is a big part of the infrastructure most people never see behind a wallet interface that just feels instant.
Why this design makes sense
It might seem simpler if every wallet had to run its own full node. But that would put a real barrier in front of anyone who wants to use a blockchain network, requiring dedicated hardware and constant syncing just to check a balance. Separating "running the network" from "talking to the network" is what makes it possible for a lightweight app on your phone to interact with Base at all. RPC endpoints are the layer that makes that separation work, quietly translating between your wallet and the chain every time you use it.
The calm summary
An RPC endpoint is the address your wallet uses to actually talk to the Base network, sending requests like balance checks and transactions and getting real answers back from a node. You rarely need to think about it, since most wallets have Base's endpoint and chain ID, 8453, built in already. If you ever do need to add it by hand, the official Base documentation is the source to check it against. And if something ever looks stuck or out of date, a slow or busy RPC endpoint is often the reason, not a sign that anything is wrong with your funds.
Sources: Connecting to Base, Base Documentation, Base RPC and Chain settings, ChainList