arXiv (independent non-profit, formerly hosted by Cornell University) · Research dissemination
Free, moderated open-access preprint server for physics, mathematics, computer science, statistics, quantitative finance, economics and related fields, with an open API and bulk access
Membership organization that registers DOIs for scholarly content and exposes the metadata through a free public REST API, content negotiation and the paid Metadata Plus service
Usage-priced market data platform with normalized order-book (MBO/MBP), trades, OHLCV and reference schemas for futures, options and equities, delivered via historical, live and batch APIs in the DBN format
Vendor of historical intraday market data (1-minute to daily bars, tick and options) for US stocks, ETFs, futures, indices, crypto and FX, delivered as zipped CSV bundles under a perpetual licence
Federal Reserve Bank of St. Louis · Market & fundamentals data
In-depth entry
Free economic database from the St. Louis Fed aggregating hundreds of thousands of US and international time series, with graphs, vintages (ALFRED), an Excel add-in and a keyed JSON/XML API
Hosting platform for open models, datasets and Spaces demo apps built on git repositories and Xet storage, with Inference Providers, Endpoints, Jobs and an open-source Python client and CLI
Open-source functional programming language and interactive theorem prover with dependent types, the Mathlib mathematics library and VS Code tooling, stewarded by the Lean FRO
Massive (Polygon.io, Inc.) · Market & fundamentals data
Market data platform (renamed from Polygon.io in October 2025) with REST and WebSocket APIs, flat files and SQL access for US stocks, options, indices, forex, crypto and futures
MathWorks' commercial numeric computing environment and language for engineers and scientists, with toolboxes, Simulink integration, apps and MATLAB Online
Nasdaq's marketplace for financial, economic and alternative datasets (formerly Quandl) with a REST API, time-series and table endpoints and Python, R and Excel clients
Bloomberg L.P. (FIGI Registration Authority) · Market & fundamentals data
Free API and web tool from Bloomberg for mapping tickers, ISINs, CUSIPs and other identifiers to public-domain FIGI instrument identifiers, with search and filter endpoints
Non-profit registry of persistent researcher identifiers (ORCID iDs) with user-controlled records, Public and Member APIs, OAuth sign-in and an annual CC0 public data file
Center for Open Science · Reproducibility & research software
Free, open-source research management platform from the Center for Open Science for projects, preregistrations, registries, preprint services and linking outputs across storage providers
Collaborative online LaTeX editor with real-time co-editing, templates and reference-manager sync, available as a hosted service and an AGPL self-hosted edition