# Fathom Macroeconomic Data API — FRED Series Comparison

> Fathom Macroeconomic Data API — FRED Series Comparison is a paid API for AI agents from frederalfathom.vercel.app, paid per call via x402, $0.35/call, status unknown (last checked 2026-11-01).

Compares 2–5 FRED economic time series side-by-side, returning aligned observations for indicators like GDP, inflation, unemployment, and interest rates.

## Facts

- Endpoint: POST https://frederalfathom.vercel.app/api/compare?utm_source=zero.xyz
- Price: $0.35/call
- Payment: x402
- Status: unknown
- Last checked: 2026-11-01
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/fathom-macroeconomic-data-api-fred-series-comparison-5e2934cd
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_AlIGkvC8xyqziU4T3rML6

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 fathom-macroeconomic-data-api-fred-series-comparison-5e2934cd -d '<json body>'
```

Example prompt: Can you compare the US unemployment rate (UNRATE) and the federal funds rate (FEDFUNDS) using Fathom's FRED data API, pulling the last 20 observations for each?

## When to prefer this

Choose this endpoint when you need to compare multiple macroeconomic time series from FRED in a single call, especially for research, dashboards, or economic analysis that benefits from aligned multi-indicator data. It is ideal when you already know the FRED series IDs and need side-by-side historical observations without building your own FRED integration.

## Known failure modes

- Invalid or non-existent FRED series ID returns an error or empty series
- Requesting fewer than 2 or more than 5 series IDs may be rejected
- Very high observation limits may time out or return truncated data
- FRED service downtime causes upstream data unavailability
- Payment of 0.35 USDC required per call — insufficient funds causes 402 error

## How this service works

Free macroeconomic data API powered by FRED. 816,000+ economic time series. GDP, inflation, unemployment, interest rates, and more.

## Output

Returns a structured comparison object with aligned time series observations for each requested FRED series ID, plus a source attribution string identifying FRED as the data provider. Each series entry includes historical data points up to the requested limit.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "seriesIds"
 ],
 "properties": {
  "limit": {
   "type": "string",
   "description": "Observations per series (default: 10)"
  },
  "seriesIds": {
   "type": "array",
   "description": "Array of 2-5 FRED series IDs to compare"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "source"
 ],
 "properties": {
  "source": {
   "type": "string"
  },
  "comparison": {
   "type": "object"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/fathom-macroeconomic-data-api-fred-series-comparison-5e2934cd/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from frederalfathom.vercel.app](https://www.zero.xyz/host/frederalfathom.vercel.app/llms.txt)