CORE API: Search 260M+ Scientific Papers Across All Repositories (Free)

#python #api #research #tutorial

Most academic APIs cover a single source. But what if you need to search across ALL of them at once?

CORE (core.ac.uk) aggregates 260M+ papers from 10,000+ repositories worldwide. It is the largest collection of open-access research papers. And it has a free API.

What Is CORE?

CORE stands for COnnecting REpositories. It harvests papers from:

University repositories (Harvard, MIT, Oxford)
Preprint servers (arXiv, bioRxiv, medRxiv)
Open-access journals (PLOS, MDPI, Frontiers)
National repositories (PubMed Central, HAL)

Result: 260M+ metadata records and 36M+ full-text papers searchable through one API.

Getting Started

Get a free API key from core.ac.uk/services/api.

import requests

API_KEY = "your_free_api_key"
BASE = "https://api.core.ac.uk/v3"
headers = {"Authorization": f"Bearer {API_KEY}"}

response = requests.get(f"{BASE}/search/works", headers=headers, params={
    "q": "web scraping ethics",
    "limit": 5
})

for paper in response.json()["results"]:
    print(f"Title: {paper[chr(39)+title+chr(39)]}")
    print(f"Year: {paper.get(chr(39)+yearPublished+chr(39), chr(39)+N/A+chr(39))}")
    print()

Find Full-Text Papers

This is CORE killer feature — actual full-text access:

response = requests.get(f"{BASE}/search/works", headers=headers, params={
    "q": "machine learning interpretability",
    "limit": 5,
    "has_full_text": "true"
})

for paper in response.json()["results"]:
    text_preview = paper.get("fullText", "")[:200]
    print(f"{paper[chr(39)+title+chr(39)]}")
    print(f"  Preview: {text_preview}...")

CORE vs Other Academic APIs

Feature	CORE	OpenAlex	Semantic Scholar	PubMed
Papers	260M+	250M+	200M+	35M+
Full Text	36M+	Links only	Links only	PMC only
API Key	Free	None needed	Free	None needed
Multi-source	10K+ repos	Aggregated	CS-focused	Biomedical