Academic Paper Search: OpenAlex, PubMed, arXiv

Academic Paper Search searches OpenAlex, PubMed and arXiv in one run and returns a single deduplicated list of papers with DOI, abstract, citation count and open-access PDF links. Enter a search query, pick a year range, and download the results as JSON, CSV or Excel.

Unofficial tool. Not affiliated with, endorsed by, or sponsored by OpenAlex, the U.S. National Library of Medicine / NCBI (PubMed), or arXiv.

What does Academic Paper Search do?

• Queries up to three scholarly databases (OpenAlex, PubMed, arXiv) with one input.
• Merges the results and removes duplicates (matched by DOI, then PMID, then arXiv ID, then a careful title match), so the same paper found in two sources appears once.
• Adds a foundIn field that lists every source where the paper was found.
• Uses each source's official public API only. No login and no proxy.
• Runs on Apify: call it via API, schedule runs, export to JSON, CSV or Excel, and connect integrations.

Who is it for?

Researchers and grad students: start a literature review from one merged list instead of three separate searches. Biotech and pharma analysts: track new papers on a topic across biomedical and preprint sources. AI teams: collect paper metadata and abstracts to build RAG corpora, ready for a spreadsheet or vector store.

What data can you get from OpenAlex, PubMed and arXiv?

One dataset item per paper. Missing values are null; empty lists are [].

Field	Type	Description
title	string (rarely null)	Paper title
doi	string or null	The paper's DOI, lowercase, without the https://doi.org/ prefix. arXiv-only papers get their arXiv DOI (10.48550/arxiv.<id>); a publisher DOI wins when both exist
pmid	string or null	The paper's PubMed ID
arxivId	string or null	The paper's arXiv ID
openalexId	string or null	The paper's OpenAlex work ID
year	integer or null	Publication year
publishedDate	string or null	Publication date as YYYY-MM-DD, YYYY-MM or YYYY
authors	list of strings, can be []	Author names
venue	string or null	Journal or venue; arXiv for preprints
abstract	string or null	Paper abstract
citedByCount	integer or null	Number of citations. Comes from OpenAlex only; null otherwise
isOpenAccess	boolean or null	Whether the paper is open access. Null for PubMed papers with no PubMed Central copy (unknown)
oaPdfUrl	string or null	Link to an open-access PDF
concepts	list of strings, can be []	Topics for the paper. For arXiv these are category codes such as q-bio.GN
foundIn	list of strings, never empty	Which sources returned this paper
sourceUrl	string, rarely null	Link to the record on its source
scrapedAt	string (ISO timestamp)	When the record was collected

Why can pmid be filled when foundIn is only openalex? foundIn lists the sources whose search returned the paper. OpenAlex records often include the paper's PubMed ID, so pmid can be filled even when PubMed's own search did not return that paper.

Sources and licenses

Source	Access method	Published rate limit	What the Actor does	Data license / terms
OpenAlex	Official OpenAlex API (api.openalex.org/works)	10 requests/s without a key (OpenAlex)	About 8 requests/s, with or without a key	Data is CC0 (OpenAlex about: Open data, OpenAlex license)
PubMed	Official NCBI E-utilities API (esearch + efetch, docs); PubMed web pages are not used	3 requests/s without a key, 10 with one (NCBI)	About 2.9 requests/s without a key, 9 with one	NCBI policies: some material may be protected by copyright, and users are expected to follow the copyright holder's terms. PubMed abstracts may be covered by publisher copyright
arXiv	Official arXiv API (export.arxiv.org/api/query)	1 request every 3 seconds (arXiv API Terms of Use)	1 request every 3.1 seconds	Metadata usable under CC0 1.0 (arXiv API Terms of Use)

Without a key, OpenAlex gives each IP address a small daily budget. If it runs out, the run continues with PubMed and arXiv only. We recommend a free OpenAlex key: it raises your daily OpenAlex budget 10× (a free key gets $1 a day) and lets the Actor use cursor paging. Without a key it uses page-by-page paging, which also reaches the 10,000-per-source maximum, so no results are lost. It does not make the Actor faster; the Actor runs at about 8 requests/s either way.

You are responsible for how you use the data.

How to use Academic Paper Search

1. Open the Actor and click Start.
2. Enter your search query, e.g. a topic like "CRISPR".
3. Choose sources (OpenAlex, PubMed, arXiv) and a year range.
4. Set Max results (per source) to cap the number of papers and the cost.
5. Start the run, then download the dataset as JSON, CSV or Excel, or fetch it via the Apify API.

Input

Field	Required	Default	Description
query	Yes	none (prefill: "CRISPR")	Search terms, e.g. a topic or keyword. Sent to each source's own search (OpenAlex search, PubMed search terms, arXiv all-fields search), so matching can vary by source
sources	No	all three (openalex, pubmed, arxiv)	Which databases to search. Select at least one
fromYear	No	empty (no lower bound)	Earliest publication year. Leave empty to skip this bound
toYear	No	empty (no upper bound)	Latest publication year. Leave empty to skip this bound. If both years are empty, there is no year filter
maxResults	No	100	Maximum papers per source (1 to 10,000); caps cost
dedupe	No	true	Merge the same paper found in several sources
openAlexApiKey	No	none	Free OpenAlex API key (secret). Recommended
ncbiApiKey	No	none	NCBI API key (secret). Raises PubMed from 3 to 10 requests/s
contactEmail	No	none	Optional email passed to NCBI and OpenAlex as a polite contact.

Example input:

{"query":"CRISPR","sources":["openalex","pubmed","arxiv"],"maxResults":10}

On Apify this returned 30 items (10 per source) in 2.7 seconds.

Output example

Three real records from the example run above. Abstracts are trimmed.

{"title":"The Heroes of CRISPR","doi":"10.1016/j.cell.2015.12.041","pmid":"26771483","arxivId":null,"openalexId":"W2239190724","year":2016,"publishedDate":"2016-01-01","authors":["Eric S. Lander"],"venue":"Cell","abstract":null,"citedByCount":493,"isOpenAccess":true,"oaPdfUrl":"http://www.cell.com/article/S0092867415017055/pdf","concepts":["Biology","CRISPR","Computational biology","Genetics","Evolutionary biology"],"foundIn":["openalex"],"sourceUrl":"https://openalex.org/W2239190724","scrapedAt":"2026-10-30T19:31:48.805Z"}

{"title":"Genome modification by CRISPR/Cas9.","doi":"10.1111/febs.13110","pmid":"25315507","arxivId":null,"openalexId":null,"year":2014,"publishedDate":"2014-11-07","authors":["Yuanwu Ma","Lianfeng Zhang","Xingxu Huang"],"venue":"The FEBS journal","abstract":"Clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR-associated protein (Cas)9-mediated genome modification enables us to edit the genomes…","citedByCount":null,"isOpenAccess":null,"oaPdfUrl":null,"concepts":["Animals","CRISPR-Associated Proteins","Clustered Regularly Interspaced Short Palindromic Repeats","Genetic Engineering","Humans","RNA Editing"],"foundIn":["pubmed"],"sourceUrl":"https://pubmed.ncbi.nlm.nih.gov/25315507/","scrapedAt":"2026-10-30T19:31:48.805Z"}

{"title":"Investigating the genomic background of CRISPR-Cas genomes for CRISPR-based antimicrobials","doi":"10.48550/arxiv.2202.07171","pmid":null,"arxivId":"2202.07171","openalexId":null,"year":2022,"publishedDate":"2022-02-15","authors":["Hyunjin Shim"],"venue":"arXiv","abstract":"CRISPR-Cas systems are an adaptive immunity that protects prokaryotes against foreign genetic elements…","citedByCount":null,"isOpenAccess":true,"oaPdfUrl":"https://arxiv.org/pdf/2202.07171v1","concepts":["q-bio.GN"],"foundIn":["arxiv"],"sourceUrl":"https://arxiv.org/abs/2202.07171","scrapedAt":"2026-10-30T19:31:48.805Z"}

The first record has a pmid although foundIn is only openalex: OpenAlex supplied the PubMed ID.

How much does it cost to search academic papers?

You pay only for papers saved to your dataset.

Event	When it is charged	Price
Actor start	Once per run	$0.00005
Paper returned	Each paper saved to the dataset	$0.0015 ($1.50 per 1,000)

Example: one run that returns 1,000 papers costs $0.00005 + (1,000 × $0.0015) = $1.50005, about $1.50. A run with 100 papers costs about $0.15.

Because Max results applies per source, the number of papers depends on how many sources you select. Deduplication can lower the count, so these are upper bounds:

• Prefilled run (all 3 sources, Max results 10): up to 30 papers, about $0.045 plus the $0.00005 start fee.
• Default Max results (all 3 sources, 100 each): up to 300 papers, about $0.45 plus the $0.00005 start fee.

The Actor respects the maximum cost you set for the run (Apify's standard spending limit): when the limit is reached it stops saving papers, logs a warning and finishes normally.

Platform usage (compute, proxy, storage) is included in these prices. You pay only the event prices listed above, nothing extra on top.

Works on Apify's free plan; you pay a tiny start fee plus only for results returned (each paper saved to your dataset). Charges come out of your Apify account's prepaid usage; on the Free plan, once that monthly usage is used up, runs stop until the next billing cycle.

Limits

• Runs stay under each source's published rate limit (see Sources and licenses). arXiv is the slowest source, at one request every 3.1 seconds.
• Without your own OpenAlex key, OpenAlex's small per-IP daily budget applies; if it runs out, the run continues with PubMed and arXiv only.
• Metadata and abstracts only. The Actor links to open-access PDFs but does not download full texts.
• Some fields are empty for some sources: citedByCount comes only from OpenAlex, and isOpenAccess is null for PubMed papers with no PubMed Central copy.
• PubMed abstracts may be covered by publisher copyright. Check reuse rights before republishing them.
• Maximum results per run: 10,000 per source, so up to 30,000 papers before deduplication.

FAQ

Is it legal to use this data? The Actor reads public metadata through each source's official API. OpenAlex data is CC0 and arXiv metadata is usable under CC0 1.0; PubMed abstracts may be covered by publisher copyright, so check reuse rights before republishing them (see NCBI policies). You are responsible for how you use the data. This is not legal advice.

Do I need an API key? No, all three sources work without keys. We recommend a free OpenAlex key: it raises your daily OpenAlex budget 10× (a free key gets $1 a day) and lets the Actor use cursor paging; without one, page-by-page paging still reaches the full 10,000 results per source. Without a key, the small per-IP daily budget applies; if it runs out, the run continues without OpenAlex. A key does not change speed: the Actor runs at about 8 requests/s either way. An NCBI key raises PubMed from 3 to 10 requests/s.

How does deduplication work? With dedupe on, records are merged when they share a DOI, then a PMID, then an arXiv ID. As a last step, a careful title match merges records whose normalized titles match (at least 25 characters), whose years are at most one apart, and whose DOIs don't conflict. arXiv-only papers keep their arXiv DOI (10.48550/…); when a publisher DOI also exists, the publisher DOI wins. foundIn lists every source that returned the paper. Merges are transitive (if A matches B and B matches C, all three become one record). Each field comes from the first source that has it, in the order OpenAlex, PubMed, arXiv; the first source's abstract is kept unless another source's is more than 20% longer, the higher citation count is kept, and concepts are combined. OpenAlex concepts are included only when they score 0.3 or higher.

Where can I see how each source did? Each run writes an OUTPUT record to its key-value store with each source's status (ok, failed or skipped) and its item count. The run's status message shows the same summary.

What search syntax can I use? Your query goes to each source's own search, so syntax differs:

• OpenAlex searches title, abstract, full text and keywords, and supports AND, OR, NOT, parentheses and "quoted phrases". A leading minus (-word) does not exclude.
• PubMed accepts full PubMed syntax, including field tags such as [tiab] and [au].
• arXiv passes field prefixes (ti:, au:, abs:, cat:) through as written. Otherwise each word becomes all:word, joined with AND. arXiv has no NOT.

Why did I get fewer papers than Max results × sources? Duplicates were merged, or the sources returned fewer matches for your query and year range.

Can I use it via API or integrations? Yes, like any Apify Actor, through the API tab, schedules and integrations.

Do I pay for Apify compute on top? No. Platform usage is included. You pay only the listed event prices: $0.00005 per run start and $0.0015 per paper.

Something broke or a field is missing? Open an issue in the Issues tab.

Changelog

• 0.1 (Unreleased): Initial release. Searches OpenAlex, PubMed and arXiv in one run with a per-source result limit and an optional year range; merges duplicates by DOI, PMID, arXiv ID and a careful title match, with foundIn showing every source; optional OpenAlex and NCBI API keys and a contact email; stays under each source's published rate limit; pay per event at $0.0015 per paper.

Disclaimer

Academic Paper Search is an unofficial tool built by Bravona. It is not affiliated with, endorsed by, or sponsored by OpenAlex, the U.S. National Library of Medicine / NCBI (PubMed), or arXiv. All product names and trademarks belong to their owners and are used only to describe compatibility. The Actor reads publicly available data through official public APIs without logging in, and follows each source's published rate limits. Data is provided as-is; accuracy and availability depend on the source. You are responsible for using the data in line with the source's terms and applicable law (including privacy law).