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Research & tools · 8 min read · 5 steps · Updated Invalid Date

How to use FRED for inflation research: a practical guide

1

FRED hosts over 800,000 data series. For inflation research, the key series to bookmark:

  • CPIAUCSL — US CPI for All Urban Consumers, seasonally adjusted, monthly. The headline US CPI series.
  • CPILFESL — US CPI less food and energy (core CPI), seasonally adjusted.
  • PCEPI — PCE price index (headline), the Fed's inflation measure.
  • PCEPILFE — Core PCE price index (ex-food and energy). This is the Fed's 2% target series.
  • T10YIE — 10-year TIPS breakeven (market inflation expectations, daily).
  • MICH — University of Michigan 1-year inflation expectations (survey, monthly).

Tip: FRED's search works well with series IDs (type the code directly) or with keywords. Use the "Units" dropdown to switch between index levels, percent changes, and year-on-year percent changes — the most common format for inflation analysis.

2

FRED series come in several formats. For inflation analysis you almost always want the "Percent Change from Year Ago" (year-on-year) view, not the index level. To convert:

  1. Open any series page (e.g., CPIAUCSL).
  2. Click the "Edit Graph" button below the chart.
  3. Under "Units", select "Percent Change from Year Ago".
  4. Click "Apply" — the chart now shows the year-on-year inflation rate.

Alternatively, append ?units=pc1 to the FRED URL for "Percent Change from Year Ago", or use the FRED graph builder to specify units programmatically. For the FRED API, use the units=pc1 parameter: https://api.stlouisfed.org/fred/series/observations?series_id=CPIAUCSL&units=pc1&api_key=YOUR_KEY.

3

FRED's "Add Line" feature lets you overlay multiple inflation series on a single chart — essential for comparing headline vs core, or CPI vs PCE:

  1. Open the CPIAUCSL series page and set units to "Percent Change from Year Ago".
  2. Click "Edit Graph" → "Add Line".
  3. Search for CPILFESL (core CPI) and click "Add series".
  4. Optionally add PCEPILFE (core PCE) for the Fed's preferred measure.
  5. Click "Save & Share" to get a permanent shareable URL.

You can also compute a custom series: click "Add Line" → "Create your own data transformation". FRED supports arithmetic operations between series, enabling calculations like the CPI-PCE gap or shelter vs non-shelter contributions.

4

FRED data is freely downloadable in multiple formats:

  • CSV download: Click "Download" → "CSV" on any series page. The file includes series metadata and all observations.
  • Excel download: Click "Download" → "Excel". Includes the same data with column headers.
  • FRED API: FRED API documentation — REST API returning JSON or XML. Example call for CPI data: https://api.stlouisfed.org/fred/series/observations?series_id=CPIAUCSL&api_key=YOUR_KEY&file_type=json
  • Python (fredapi): pip install fredapi — the official Python wrapper. Two lines to get CPI data: from fredapi import Fred; fred = Fred(api_key='YOUR_KEY'); cpi = fred.get_series('CPIAUCSL')

The FRED API also supports bulk category downloads, series search, and vintage data (historical snapshots as of past dates) — useful for replicating historical forecasts.

5

A practical inflation monitoring dashboard using FRED typically includes:

  • Panel 1 — Headline vs core: CPIAUCSL and CPILFESL (year-on-year), last 5 years. Add a horizontal line at 2% for the target.
  • Panel 2 — CPI vs PCE: CPIAUCSL and PCEPILFE, same window. Shows the typical 0.3–0.5 pp gap and how it behaves during inflation episodes.
  • Panel 3 — Market expectations: T10YIE (10-year TIPS breakeven) and MICH (Michigan 1-year survey), both on the same chart. Shows whether long-run expectations are anchored.
  • Panel 4 — Shelter component: CPIHOSSL (shelter CPI) alongside CUSR0000SAH1. The most important leading indicator of future core CPI normalisation.
  • Panel 5 — Real policy rate: DFF (fed funds rate) minus CPIAUCSL percent change. When this is positive, monetary policy is restrictive in real terms.

Save each as a FRED "My Graph" (requires free registration). FRED also supports custom dashboards that combine multiple saved graphs in one view, updated automatically. Our real-time tracking guide expands on this with additional non-FRED sources.

Sources & further reading

Terms in this guide

consumer price index cpi core inflation real interest rate pce price index base effect

Frequently asked questions

Is FRED free to use and what are the terms?
FRED is entirely free — no subscription required for the website and basic API access. The API requires a free registration to obtain an API key, which has rate limits (120 requests per minute) generous enough for most personal and research use. Data is published under a FRED Terms of Use that permits research, education, and publication with attribution. Commercial use of the data is also permitted under the same terms.
What is the difference between seasonally adjusted and unadjusted CPI on FRED?
Seasonally adjusted CPI (CPIAUCSL) removes predictable seasonal patterns — e.g., clothing prices always rise in autumn, hotel prices always spike in summer. The adjustment makes month-on-month changes meaningful by stripping out this predictable calendar effect. Unadjusted CPI (CPIAUCNS) is the raw data. For year-on-year analysis, the difference is minimal (seasonal effects cancel out). For month-on-month analysis, always use seasonally adjusted. The BLS explains its seasonal adjustment methodology in detail.
Does FRED have international inflation data?
Yes — FRED carries inflation data for many countries beyond the US, sourced from the World Bank, OECD, Eurostat, and national statistics agencies. Search for "CPI" plus the country name, or browse the FRED International Data category. For the broadest cross-country annual data, the World Bank WDI (which our inflation explorer uses) covers 180+ countries with a single API call.