Free alternative data sources

Reviewed 2026-10-15

Free alternative data sources for filings, hiring, economic history, satellite imagery and web research, with access details and commercial-use limits.

Which free source should you start with?

Start with SEC EDGAR for company filings, FRED and ALFRED for economic series and historical vintages, Indeed Hiring Lab for aggregate hiring trends, USGS Landsat for satellite observations, and Common Crawl for archived web content. These sources answer different questions: an economic index cannot replace a company-level hiring feed, and a satellite scene is not a ready-made revenue estimate.

This list includes both alternative observations and conventional public benchmarks used alongside them. Free access, an open licence and unrestricted commercial use are separate properties. The sections below identify what is available and where service conditions matter, rather than treating every public website as a free production API.

SEC EDGAR: company filings and financial facts

SEC EDGAR provides submissions history and extracted XBRL facts through JSON APIs without an API key. The SEC also publishes nightly bulk archives, which are more practical than thousands of individual requests for an initial download. Submissions are addressed by the company's ten-digit Central Index Key, or CIK.^[1]

The submissions response includes current company names, exchanges and ticker symbols where applicable. It is therefore incorrect to say that free data never includes ticker mapping. However, current symbols do not constitute a historical security master: mergers, renamed issuers and multiple share classes still need date-aware treatment. For research, retain the filing identifier and its publication timing rather than assigning a fact to the end of the quarter it describes. Follow the SEC's automated-access guidance when retrieving files.^[1]

FRED and ALFRED: economic series with revision history

FRED is useful for economic benchmarks. Its API requires a registered key. ALFRED adds a crucial research distinction: what a series looked like at a past date. The real-time start and end parameters select when information was known; a normal request defaults to information available today.^[2]

Use a vintage query when testing a decision made before a later statistical revision. Save the series identifier, observation period, requested vintage and download date. A long historical series downloaded today is not automatically the series an investor saw at the time. The point-in-time guide gives a worked example of that difference. Review the source and terms attached to each series rather than assuming that every series in an aggregator has identical reuse conditions.

BLS, Census and Indeed: labour and economic context

The Bureau of Labor Statistics' JOLTS programme distinguishes job openings, hires and separations. Openings are measured on the last business day of the month, while hires are additions to payroll during the month. This makes JOLTS a useful benchmark, but not an interchangeable substitute for daily advertisements collected from websites.^[3]

Indeed Hiring Lab publishes downloadable job-posting indexes by country and, where available, sector and region. The repository describes daily observations refreshed weekly and grants reuse under CC BY 4.0 with attribution. It supplies aggregate indexes, not a free export of individual Indeed advertisements. Its documentation also records revisions to historical seasonal adjustment, which matters for backtests.^[4]

The Census API provides demographic and economic statistics for geographic comparisons. Its terms specify attribution and prohibit attempts to identify respondents. Aggregate local conditions can help interpret a retailer's exposure, but they do not reveal that retailer's own sales. Match the geographic units and reporting periods before joining Census statistics to company locations.^[5]

Landsat: free imagery, separate processing costs

USGS makes Landsat archive products available to download at no cost. EarthExplorer supports searches by location and date, while cloud access and the Machine-to-Machine API support larger workflows. Products include surface reflectance and surface temperature, so choose the processing level needed for the research question.^[6]

The imagery still needs cloud filtering, geographic alignment and a measurement procedure. For example, vegetation change over a defined agricultural area is a different task from counting small objects at a factory. Check spatial resolution and usable observations before choosing a product. Satellite and geospatial signals explains those trade-offs.

Google Earth Engine is a processing platform, not a blanket free-commercial licence for working with those images. Google provides free access for eligible noncommercial uses and charges for commercial use. The conditions of a hosted analysis platform are separate from the access conditions of the underlying satellite archive.^[7]

Open-Meteo: distinguish the data licence from API access

Open-Meteo offers weather APIs, but the free hosted API is for noncommercial use and has request limits. Commercial subscriptions provide a customer endpoint and access key. Its weather data uses CC BY 4.0; that data licence and the conditions for using the hosted service answer different questions.^[8]

For a commercial weather-sensitive demand model, budget for the service you will actually use. Also distinguish observed historical weather from historical forecasts: a later reconstruction of what happened does not represent what a forecaster knew before the event. Select the appropriate product and retain its run or release time.

Common Crawl: archived pages for web research

Common Crawl provides free HTTP access to crawl archives without requiring an AWS account for that access method. WARC files contain captured responses, WAT files contain derived metadata, and WET files contain extracted text. Choose the smallest format that preserves the evidence your project needs.^[9]

A sensible pilot starts with a narrow domain and date range rather than downloading an entire crawl. Preserve the original URL and capture time with extracted fields. Missing captures do not prove that a company had no product, job or price on that date, and an archive does not guarantee complete coverage or permission to republish every captured page.

Turn a free source into a usable research input

Write down the required observation unit first: company, establishment, region, individual posting or image pixel. Then test a small extract against that requirement. Record identifiers, units, timestamps, missing values and revision behaviour. A dataset with the right subject but the wrong observation unit can be unusable even when every row is accurate.

Some public sources are suitable for production; others need a paid service or substantial processing. Compare the actual operating costs rather than assuming free data is only for prototypes or that a paid feed is automatically better. Use the pricing guide for a cost worksheet and the catalogue to find further records. Catalogue metadata helps discovery; the source determines access and reuse terms.