Pair US consumer prices with country economics, release calendars, public holidays and FX through Narwhal. One account connects REST requests and hosted MCP tools. Massive, formerly Polygon.io, offers a US inflation endpoint alongside its stocks, options and other market-data products.
Choose Narwhal to build country dashboards and calendar workflows around one economics catalogue, with a free commercial allowance shared by your application and agent.
The shared job is US consumer-price data; Massive's inflation endpoint also includes PCE measures.
| Requirement | Narwhal API | Massive (formerly Polygon.io) |
|---|---|---|
| Free tier | ✓ 3,000 requests/month | ✓ Stocks Basic: 5 calls/minute |
| Cheapest paid plan | Basic: $60/month; $600/year available | Stocks Starter: $29/month |
| Update speed | Dataset schedule; timestamps retained | Inflation: monthly; free stocks: end of day |
| History | Free: 12 months; Basic: 5 years; available records only | Inflation: from 1947; free stocks: 2 years |
| Coverage | Economics, FX, holidays and published commodities | US inflation and market data |
| Interfaces | REST and MCP; WebSocket not published | REST, WebSocket, flat files and MCP |
| SDKs | Not published | ✓ Official clients in documentation |
| Commercial use on free tier | ✓ Commercial apps; resale needs Enterprise | ✗ Individual use |
Inflation is included in the free individual plan, with requests spread across its five-call minute limit.
| Requests per month | Narwhal API | Massive (formerly Polygon.io) |
|---|---|---|
| 1,000 | Free: $0/month | Stocks Basic: $0 |
| 10,000 | Basic: $60/month | Stocks Basic: $0 |
| 100,000 | Basic: $60/month | Stocks Basic: $0 |
Read US consumer prices
# Change: URL and key
curl --get \
"https://api.massive.com/fed/v1/inflation" \
--data-urlencode "limit=1" \
--data-urlencode "sort=date.desc" \
--data-urlencode "apiKey=YOUR_API_KEY"# Change: URL and key
curl \
"https://api.narwhalapi.com/v1/economics/USA/cpi" \
-H "Authorization: Bearer YOUR_API_KEY"Narwhal Free includes 3,000 successful requests each month and permits commercial apps. Use that allowance for a dashboard, scheduled data fetches or an agent integration. Move to Basic for 100,000 monthly requests as usage grows, with the same account and authentication.
REST and hosted MCP reach the same data through one account. Your application can fetch JSON while an agent uses the hosted tools, with every successful call counted once against the shared allowance. One quota makes the combined workload straightforward to budget.
Narwhal's economics catalogue spans 36 countries, with a coverage table for each indicator. Country and indicator paths organize requests around the data your application uses. Combine observations with FX, public holidays and release dates to build country dashboards through the same account.
Massive is the better pick for stock or options data, WebSocket streams and flat files. Its inflation endpoint includes CPI and PCE measures, monthly updates and records from 1947. That endpoint is included in all individual plans, including the free Stocks Basic plan. For a personal US inflation project, that free access is a strong option; business licensing is separate.
Yes. Narwhal Free includes 3,000 successful requests per month, commercial app use and both REST and hosted MCP access. US CPI is available through a country-specific endpoint alongside Narwhal's wider economics catalogue.
Polygon.io became Massive on October 30, 2025. Its announcement says the new and old API hostnames run in parallel and existing keys continue to work. New examples here use the hostname in Massive's current documentation.
Replace the request URL and authentication, then map the JSON response into your application's fields. The examples use standard fetch in JavaScript and requests in Python, so integration fits an ordinary HTTP client. Keep your key on the server and carry the response's units, dates and missing values into your display or calculations.
The shared cap applies to successful REST and MCP requests together. There are no automatic overage charges. Basic includes 100,000 monthly requests; quotas reset each month even when you pay yearly.
The comparison uses Narwhal's current public contract and the following first-party competitor pages.
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