> ## Documentation Index
> Fetch the complete documentation index at: https://docs.algovoi.co.uk/llms.txt
> Use this file to discover all available pages before exploring further.

# Base USDC payments

> Accept USDC (ERC-20) on Base: EVM native settlement, amount only binding, and x402 payment facilitation on both Base mainnet and Base Sepolia testnet.

## At a glance

|                     | Mainnet                                      | Sepolia (testnet)                            |
| ------------------- | -------------------------------------------- | -------------------------------------------- |
| Network ID          | `eip155:8453`                                | `eip155:84532`                               |
| Native asset        | ETH                                          | ETH                                          |
| Native decimals     | 18                                           | 18                                           |
| Stablecoin          | USDC ERC-20                                  | USDC ERC-20                                  |
| Stablecoin contract | `0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913` | `0x036CbD53842c5426634e7929541eC2318f3dCF7e` |
| Stablecoin decimals | 6                                            | 6                                            |
| Confirmation time   | About 2 seconds                              | About 2 seconds                              |
| Typical fee         | \$0.001 to \$0.05                            | Free (Sepolia faucet)                        |

## Amount-only binding

Base is EVM, and EVM ERC-20 transfers don't carry a memo. AlgoVoi binds Base checkouts to specific links by **amount uniqueness**. Each checkout generates a slightly randomised amount (within 0.000001 USDC of the target) so two open checkouts for the same amount can be distinguished by their actual on-chain transfer values.

This means:

* A Base checkout's amount in the JSON response is what your customer must send exactly.
* Don't strip cents or round.
* The link's `amount_microunits` is authoritative.

## Payout addresses

Standard Ethereum-format addresses (40 hex chars, optional `0x` prefix). EIP-55 mixed-case checksumming is supported but not required. Base uses the same addresses as Ethereum mainnet, so an address you control on mainnet works on Base out of the box (different state, same identity).

## Wallets

* [AlgoVoi Chrome extension](https://chromewebstore.google.com/detail/algovoi/ofmgegnkjdmbeakjbmfaagigmhagdcbl) (in-house wallet, native x402 / MPP / AP2 on Base via viem `signTransaction` + ERC-20 `transfer` for USDC; six-chain coverage as of v2.6.0)
* [Coinbase Wallet](https://wallet.coinbase.com)
* [Rainbow](https://rainbow.me)
* [MetaMask](https://metamask.io) (with Base added as a custom network)

## Agent-to-agent settlement on Base

Base is where x402 began, Coinbase's EVM Layer 2 and the first home of HTTP 402 stablecoin payments for agents. AlgoVoi Mesh adds what x402 alone does not carry: mutual post-quantum authentication between the two agents, verified offline before anything settles.

[AlgoVoi Mesh](/agent-mesh) settles a payment directly between two autonomous agents on Base. Each agent verifies the other offline with a Falcon-1024 credential, the pair negotiates Base as the settlement chain, and the authorized decision is anchored in the transaction calldata as one content-addressed `execution_ref`. There is no facilitator, no per-transaction fee, and no AlgoVoi service in the trust path at settlement time.

**Proven on-chain.** A mutually verified Falcon-1024 pair negotiated Base and settled once:

| Network      | Anchors in | Transaction                                                                                                         |
| ------------ | ---------- | ------------------------------------------------------------------------------------------------------------------- |
| Base Sepolia | calldata   | [0x3d4165a9...](https://sepolia.basescan.org/tx/0x3d4165a94bb20a7b1a62e7f285bb64f0fb986deada00414b475eea7e611a0b8b) |

The transaction calldata carries the 32 byte `execution_ref` that run's handshake produced. Recompute it yourself from the raw fields with a stock RFC 8785 (JCS) implementation and SHA-256 and compare; no AlgoVoi software is involved in checking it.

The chain never verifies Falcon. It only carries the anchor, which is why the same agent trust works on Base and on every other chain the pair could have chosen. See [AlgoVoi Mesh](/agent-mesh) for the mutual handshake, the signed chain-offer negotiation, and the full eight-chain proof.

## See also

* [Tempo](/chains/tempo) for the other EVM-style chain we support
* [x402 protocol](/protocols/x402) for the payment protocol layer