# x402 Transactions Tracker: Daily Payments and Volume

> x402 transactions per day on Base, Solana and other chains: settled payments, USDC volume, payment sizes, payers and paid services, each counted on-chain.

Markdown copy of https://voltfincrypto.com/apps/x402-transactions-tracker

**Question:** How many x402 payments settle each day, and how much value do they move on each chain?

- Kind: Dashboard in Voltfin Vantage
- Topic: [AI and agents](https://voltfincrypto.com/topics/ai-agents)
- Chains: Multi-chain, Base, Solana, Polygon, Avalanche
- Status: Planned. The data is not published yet, so this page states no figure; each figure will open its receipt when it is.

x402 is an open payment standard built on the HTTP 402 Payment Required status: a server asks for payment, the client signs a stablecoin transfer and a facilitator settles it on-chain. It lets software agents pay for API calls, data and content one request at a time. This dashboard counts those settlements from the chains themselves: how many payments land each day, how much value they move and on which chains.

Not every signed stablecoin transfer is an x402 payment, so the count starts from the addresses of known facilitators and the transfers they submit. Payments are grouped by size, which separates small pay-per-call payments from larger transfers, and by payer and payee, which shows whether activity comes from many agents or from a few.

Every figure is pinned to the blocks it was counted from, so a daily total can be traced back to the individual settlement transactions and facilitator addresses behind it.

## Blueprint

### Today

Payments, volume and payers on the latest complete day.

- **Payments settled** (count): x402 payments settled on the latest complete UTC day, counted from facilitator-submitted transfers.
- **Payment volume** (USDC): The face value of the same day's payments, summed.
- **Median payment** (USDC): The median payment amount on the same day.
- **Distinct payers** (count): Distinct addresses that paid at least once on the same day.
- **Payments by chain** (count): The day's payments split by the chain they settled on.
- **Payments by size** (count): The day's payments grouped into size buckets, from pay-per-call amounts to larger transfers.

### Trend

How payments, volume and payment sizes moved by day and by chain.

- **Payments in the period** (count): x402 payments settled over the selected period.
- **Services paid** (count): Distinct payTo addresses that received at least one payment over the period.
- **Median payment by day** (USDC): The median payment amount by day, to show whether payments are getting smaller or larger.
- **Payments and volume by day** (count): Payments per day stacked by chain, with each day's volume drawn as a line.

Filters: Chain (Every covered chain, or one of Base, Solana, Polygon and Avalanche); Period (Last 7, 30 or 90 days).

## How it will be measured

- On EVM chains, a payment is a USDC transferWithAuthorization (EIP-3009) settled by a known x402 facilitator address, read from the AuthorizationUsed and Transfer logs of the same transaction.
- Payments on the Permit2 path that x402's second version added are read from transfers through its proxy contract, and on Solana from SPL token transfers in transactions whose fee payer is a known facilitator.
- Facilitator addresses come from the facilitators' own documentation and public x402 listings, recorded with their source; transfers from unlisted senders are left out rather than guessed.
- Volume is the sum of payment amounts at face value, and sizes are grouped into buckets so that small payments are not hidden by a few large ones.
- Every figure carries a receipt: the blocks or slots, the transaction hashes and the logs it was counted from.

## Data it needs

- `agent_payments_daily` (to build): Agent tokens (supply, holders, trading) and agent payments such as x402 settlements in stablecoins, per day.
- `stablecoin_flows_daily` (to build): Stablecoin mints, burns, transfer volume and active addresses per stablecoin and chain per day.
- `address_labels` (to build): Labels for known addresses: exchanges, bridges, protocols, funds, treasuries, sanctioned addresses and known attackers.
- Source: USDC AuthorizationUsed and Transfer logs from transferWithAuthorization calls on Base, Polygon and Avalanche
- Source: Transactions sent by known x402 facilitator addresses, from a facilitator address registry
- Source: Transfers through the x402 Permit2 proxy contract for tokens without EIP-3009
- Source: Solana SPL token transfers in transactions where a known facilitator is the fee payer
- Source: Distinct payer and payTo addresses per day

## Questions

### What is x402?

x402 is an open standard, first published by Coinbase, for paying over HTTP. A server answers a request with status 402 and its price; the client signs a stablecoin payment and retries; a facilitator verifies the signature and settles the transfer on-chain, so the buyer needs no account or API key.

### Which chains does x402 run on?

x402 is chain-agnostic: a payment settles on any network that a facilitator supports for the token. It launched on Base, and facilitators have since added Solana, Polygon, Avalanche and other chains. The chain split tile shows where payments actually settle.

### What is an x402 facilitator?

The service that checks a signed x402 payment and submits it to the chain, paying the gas. Sellers choose which facilitators they accept. Because the facilitator sends the transaction, its address is how x402 settlements are recognized on-chain.

### Are all x402 transactions made by AI agents?

No. The chain records a signed payment and its settlement, not who or what signed it. Payments can come from agents, apps or people; some activity is testing or promotions. This dashboard counts settlements and distinct payers and does not claim to know which are agents.

### Why do x402 totals differ between sources?

Sources differ in which facilitators they include, whether they count test networks, which tokens they track and when they cut off a day. This dashboard lists the facilitator addresses it counts and pins every daily total to the blocks it covers.

## Glossary

- **HTTP 402**: The Payment Required status code, reserved in early HTTP for future use and adopted by x402 to ask a client for payment.
- **EIP-3009**: The transferWithAuthorization function, which lets a token holder sign a transfer that someone else submits and pays gas for. USDC supports it.
- **Facilitator**: The x402 service that verifies a signed payment and settles it on-chain on the seller's behalf.
- **payTo address**: The address named in a seller's payment requirements, which receives the stablecoin when a payment settles.

## Related apps

- [x402 Facilitators and Paid Services Ranked](https://voltfincrypto.com/apps/x402-facilitators-ranking)
- [AI Agents in Crypto: Monthly On-Chain Report](https://voltfincrypto.com/apps/ai-agents-in-crypto-monthly-report)
- [ERC-8004 Agent Registry: Registered AI Agents by Chain](https://voltfincrypto.com/apps/erc-8004-agent-registry)
- [Stablecoin Payments by Transfer Size and Chain](https://voltfincrypto.com/apps/stablecoin-payments-by-transfer-size)
- [Stablecoins on Base: Supply and Transfers](https://voltfincrypto.com/apps/stablecoins-on-base)
- [AI Agent Tokens Ranked by Holders and DEX Volume](https://voltfincrypto.com/apps/ai-agent-tokens-ranking)

Build it in Voltfin Studio: https://app.voltfincrypto.com/signup?next=%2F