# Blockchain.com Explorer - Mempool Transaction Count Chart

> Blockchain.com Explorer - Mempool Transaction Count Chart is a paid API for AI agents from api.blockchain.info, paid per call via x402, $0.001/call, status unknown (last checked 2026-10-02).

Returns time-series chart data showing the number of unconfirmed Bitcoin transactions in the mempool over a specified time period

## Facts

- Endpoint: POST https://api.blockchain.info/explorer-gateway-kt/x402/charts/mempool-count?utm_source=zero.xyz
- Price: $0.001/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-02
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/blockchain-com-explorer-mempool-transaction-count-chart-414e7fa8
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_m0YjeyRr8NGAGGTHJBmrT

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability blockchain-com-explorer-mempool-transaction-count-chart-414e7fa8 -d '<json body>'
```

Example prompt: Can you pull the Bitcoin mempool transaction count chart from Blockchain.com for the past year, using an 8-hour rolling average, and return it as JSON?

## When to prefer this

Use this endpoint when you need historical or near-real-time Bitcoin mempool transaction count data from Blockchain.com's authoritative explorer. Prefer this over generic crypto APIs when you need flexible time ranges (24h to 3y), configurable rolling averages, and structured JSON or CSV output. Ideal for agents monitoring Bitcoin network congestion, timing transactions, or performing on-chain analytics.

## Known failure modes

- Invalid timespan format returns a 400 error
- Invalid rollingAverage window value causes a bad request response
- Payment failure (402) if USDC payment is not included or insufficient
- Rate limiting or access denial if API credentials are invalid
- Empty dataset if the requested timespan has no recorded data

## How this service works

Paid AI-agent access to Blockchain.com Explorer API

## Output

A time-series dataset of Bitcoin mempool unconfirmed transaction counts, returned as JSON (with optional metadata) or CSV. Each data point includes a timestamp and the count value, optionally smoothed by a configurable rolling average window. Metadata fields may include chart name, description, and unit labels.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "cors": {
   "type": "boolean",
   "default": false,
   "description": "Enable CORS headers"
  },
  "format": {
   "enum": [
    "json",
    "csv"
   ],
   "type": "string",
   "default": "json",
   "description": "Response format:\n- `json` — Returns structured JSON with metadata and values\n- `csv` — Returns raw CSV data with timestamp and value columns (no metadata)\n"
  },
  "sampled": {
   "type": "boolean",
   "default": true,
   "description": "Apply sampling to reduce data points"
  },
  "metadata": {
   "type": "boolean",
   "default": false,
   "description": "Include metadata in response"
  },
  "timespan": {
   "type": "string",
   "default": "1y",
   "example": "1y",
   "description": "Time period (e.g., \"24h\", \"7d\", \"1y\", \"3y\")"
  },
  "rollingAverage": {
   "type": "string",
   "default": "8h",
   "example": "8h",
   "description": "Rolling average window (e.g., \"8h\", \"24h\")"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "format": "application/json",
 "example": {
  "name": "Mempool Transaction Count",
  "unit": "Transactions",
  "period": "minute",
  "status": "ok",
  "values": [
   {
    "x": 1704067200,
    "y": 18342
   },
   {
    "x": 1704068100,
    "y": 19105
   }
  ],
  "description": "The number of transactions waiting to be confirmed."
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/blockchain-com-explorer-mempool-transaction-count-chart-414e7fa8/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.blockchain.info](https://www.zero.xyz/host/api.blockchain.info/llms.txt)