Essential OJS Plugins Every Journal Should Use

OJS plugins: built-in vs the Plugin Gallery

OJS plugins extend the software: they add metadata for indexing, register DOIs, show citation formats, create pages, export content and change the design. There are three sources:

• Bundled plugins ship inside the OJS download. You will find them under Settings → Website → Plugins → Installed Plugins. Some are enabled by default; others just need a tick. They are updated whenever you upgrade OJS.
• Plugin Gallery plugins are listed under Settings → Website → Plugins → Plugin Gallery and install in one click. Each entry shows the maintainer and which OJS versions each release supports. Some are maintained by PKP; others by universities, libraries and independent developers.
• External plugins are downloaded from a developer's repository and uploaded with Upload a New Plugin. Use these only from sources you can verify.

Import/export plugins (DOAJ, Native XML, PubMed and others) appear under the Tools menu once enabled. The lists below are based on the OJS 3.3, 3.4 and 3.5 source code and the PKP Plugin Gallery at the time of writing; bundled plugins can change between releases, so check Installed Plugins on your own site.

Indexing and metadata plugins

Google Scholar Indexing Plugin (bundled)

Adds the bibliographic meta tags Google Scholar reads on each article page, such as citation_title, citation_author, citation_publication_date and citation_pdf_url. Without it, Scholar struggles to index your articles correctly. PKP has documented upgrades that left this plugin disabled, so check it after every upgrade by viewing the source of an article page. Full setup and troubleshooting are in our Google Scholar indexing guide for OJS.

Dublin Core Indexing Plugin (bundled)

Adds Dublin Core (DC.*) meta tags to article pages. Some search engines, repositories and harvesters use them. Enable it alongside the Google Scholar plugin; the two do not conflict.

OAI-PMH (built into OJS)

OAI-PMH is not a separate plugin but a core feature that lets indexing services harvest your metadata. Make sure Enable OAI is ticked under Settings → Distribution → Access. Your endpoint is usually https://yourjournal.org/index.php/abbr/oai. The Plugin Gallery also has an official OAI JATS plugin if a harvester asks for JATS XML.

DOAJ Export Plugin (bundled)

For journals already accepted into DOAJ. Under Tools → Import/Export → DOAJ Export Plugin you can export article metadata, or enter your DOAJ API key in the plugin settings to deposit records directly, with an option for automatic registration. It does not help you get accepted; that depends on your policies and practices, as explained in our DOAJ indexing guide.

PubMed XML Export Plugin (bundled)

Exports article metadata in the format PubMed uses. It is only useful for journals that NLM has approved as PubMed data providers.

DOI, Crossref and ORCID plugins

DOIs and Crossref

How DOIs work depends on your version:

• OJS 3.3: enable the bundled DOI plugin (Public Identifier plugins) to assign DOIs, and the bundled Crossref XML Export plugin under Tools → Import/Export to deposit them.
• OJS 3.4 and 3.5: DOI management is a core feature under Settings → Distribution → DOIs, with a DOIs menu for assigning and depositing. You also enable a registration agency plugin: Crossref and DataCite are bundled, and mEDRA is available in the Plugin Gallery.

You need membership of a DOI registration agency such as Crossref and your own DOI prefix. Step-by-step settings, suffix patterns and fixes for failed deposits are in our DOI and Crossref setup guide. Once DOIs work, the official Crossref Reference Linking plugin (Plugin Gallery) adds your articles' reference lists to your Crossref deposits, which supports reference linking and citation tracking.

ORCID

• OJS 3.3 and 3.4: the ORCID Profile plugin, included with OJS and updated through the Plugin Gallery, lets authors connect authenticated ORCID iDs and can send publication data to ORCID records.
• OJS 3.5: ORCID integration moved into the core software. PKP's ORCID Profile repository states the plugin is not needed and will not be updated for 3.5 and later.

Either way you need ORCID API credentials (a client ID and secret) from ORCID. PKP's ORCID guide explains the public and member API options.

Preservation and archiving plugins

Indexers and libraries want to know your content will survive if your server or publisher disappears.

• PKP Preservation Network (PKP PN) plugin (Plugin Gallery, official): deposits published issues into a distributed preservation network. According to PKP's PKP PN guide, you need OJS 3.1.2 or newer, an ISSN, at least one published article and Administrator access, and you must accept the terms of use in the plugin settings.
• LOCKSS / CLOCKSS: if your institution belongs to one of these networks, activate it under Settings → Distribution → Archiving.
• Portico plugin (Plugin Gallery, official): for journals with a Portico preservation agreement.

Preservation is not a backup. You still need daily server backups of the database, files directory and public/ folder. The official Backup plugin in the gallery lets an administrator download backups from inside OJS, which helps on small installations but does not replace automated backups.

Statistics and analytics plugins

• OJS 3.3: the bundled Usage Statistics plugin records views and downloads and can show a download chart on article pages.
• OJS 3.4 and 3.5: statistics are built in (the Statistics menu covers articles, editorial activity and users). PKP's documentation says usage is filtered using COUNTER rules for bots and repeated clicks, and COUNTER R5 reports are available through the SUSHI interface. The download chart on article pages is now a theme option in the Default theme.
• Google Analytics (bundled) and Matomo (Plugin Gallery, official) add website analytics. Mention any analytics tool in your privacy statement.

Usability and reader plugins

Enable Static Pages and Custom Block Manager on every journal: they are how you publish policies and the information indexers look for. Our journal policy templates give you text for those pages.

Editorial and import/export tools

• QuickSubmit (Plugin Gallery, official): lets journal managers add articles through a single form without running them through review. Ideal for loading back issues when you move a journal into OJS. Do not use it to bypass peer review for new submissions.
• Native XML Plugin (bundled): exports and imports issues and articles as XML, for moving content between OJS installations.
• Users XML Plugin (bundled): exports and imports user accounts.
• CRediT (Plugin Gallery for 3.4; included in 3.5): records contributor roles using the CRediT taxonomy.
• Publication Facts Label (official; included in 3.5, Plugin Gallery for earlier versions): helps readers see how an article and journal meet scholarly standards such as peer review and disclosure.
• Form Honeypot (Plugin Gallery, maintained by a university library): an extra layer against spam registrations alongside reCAPTCHA.

Plagiarism checking (iThenticate plugin)

The official iThenticate plugin (listed as "iThenticate" in the Plugin Gallery, with releases for 3.3, 3.4 and 3.5) sends uploaded submissions to iThenticate for a similarity report that editors can open from the workflow. You need your own iThenticate account; many journals get access through Crossref's Similarity Check service. Configuration differs between plugin releases, so follow the README of the release that matches your OJS version.

A similarity score is not a verdict. Editors still need to read the report, exclude references and properly quoted material, and follow the journal's plagiarism policy.

Theme plugins

Themes are plugins too. OJS includes the Default theme, and the official Manuscript, Bootstrap3, Health Sciences, Classic, Immersion and Pragma themes are free in the Plugin Gallery. Our comparison of free OJS themes explains which suits your journal. Disable themes you are not using, and never install themes from unknown download sites.

OJS plugin list at a glance

How to install and enable OJS plugins safely

1. Back up first

   Take a database backup and a copy of the plugins/ folder. Plugins can change the database.

2. Check compatibility

   Click the plugin's name in the Plugin Gallery to see its maintainer, description and supported OJS versions. For external plugins, read the README and release notes.

3. Install as Administrator

   From the Plugin Gallery click Install. For a .tar.gz from an official repository, use Installed Plugins → Upload a New Plugin.

4. Enable and configure

   Tick the plugin under Installed Plugins, then click the blue arrow next to its name and choose Settings if it has any.

5. Test

   Check the homepage, an article page and a test submission. Then clear the template cache under Administration.

6. Keep it lean

   Disable plugins you do not use. Every enabled plugin is code that must stay compatible and secure.

Check plugin compatibility before OJS upgrades

Bundled plugins are upgraded together with OJS. Plugins you added yourself are not. Before upgrading:

• List every plugin you installed from the gallery or uploaded, including themes.
• For each, confirm there is a release for the OJS version you are moving to. Major upgrades often need new plugin releases; the move from 3.3 to 3.4, when plugins switched to namespaced PHP code, broke many older plugins.
• Disable plugins with no compatible release before upgrading, and look for a maintained alternative.
• Rehearse the upgrade on a staging copy, then check the Plugin Gallery for entries marked as upgradable.
• After the upgrade, re-check Google Scholar meta tags, DOI deposits and ORCID.

An incompatible plugin is one of the most common causes of a blank page or HTTP 500 error after an upgrade. If you would rather not handle this yourself, our OJS upgrade and migration service checks plugins and themes as part of the process.

Avoid abandoned and unknown-source plugins

A plugin runs with the same access as OJS: your database, user accounts and unpublished manuscripts. Be careful with:

• Abandoned plugins: no release for your OJS version, no recent updates and unanswered issues. They will block your next upgrade.
• Unknown sources: zip files shared on forums, social media or download sites, and "nulled" copies of commercial plugins. They can contain backdoors or code that injects spam links into your journal.
• Plugins that need core file edits: any change to OJS's own files is lost at the next upgrade.
• Plugins that load external scripts you do not understand, or ask for administrator passwords.

When in doubt, ask on the PKP Community Forum or consult PKP's Plugin Inventory. If you want the right plugins configured and tested for indexing, DOIs and ORCID, our OJS services cover the full setup, and technical support is available when a plugin misbehaves.

Frequently Asked Questions