Latest, single-month, or ranged US CPI inflation data with plain-English summary.
Gives you official United States inflation numbers from the government's Consumer Price Index. Ask for the newest reading, a specific month in the past, or a whole range of months, and get back clear percentages for overall inflation and 'core' inflation (which ignores food and energy prices), plus a plain-English summary sentence.
https://cpi-report-us.underscoredone.com/cpi$0.01 per request — pay via x402/USDC. No account needed.
Send an empty body for the newest available inflation report. Send 'period' as YYYY-MM to get one specific historical month. Send 'start' and/or 'end' as YYYY-MM to get a series of months for charting or analysis; omitting both start and end while providing neither period returns the newest single report. Do not send 'period' together with 'start'/'end' — 'period' takes priority and a range will not be returned. Treat any rate field that comes back as null as simply unavailable for that month, not an error.
| Name | Type | Required | Description |
|---|---|---|---|
period | string/null | no | A single month to look up, written as year-month, like 2024-03. Leave this out if you want the newest data or a range instead. |
start | string/null | no | The first month of a historical range, written as year-month, like 2023-01. Leave out to start from the earliest available month. |
end | string/null | no | The last month of a historical range, written as year-month, like 2024-12. Leave out to end at the newest available month. |
{
"period": "2024-03"
}{}{
"period": "2099-13"
}{
"start": "1913-01",
"end": "2024-12"
}{
"api_version": "1.0.0",
"reference_period": "2024-03",
"headline_index": 314.796,
"core_index": 313.5,
"headline_yoy_pct": 3.4,
"core_yoy_pct": 3.3,
"summary": "In 2024-03, prices overall were up 3.4% compared to a year earlier, and core prices (excluding food and energy) were up 3.3% compared to a year earlier."
}| Status | Meaning |
|---|---|
400 | Bad request — your input failed validation or could not be processed. Check the detail field for specifics. |
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