Want to publish for free? A guide to diamond open access journals

Scientific journals were created to evaluate and circulate academic knowledge. In principle, they give discoveries visibility, encourage discussion among peers, and help science move forward. Yet knowledge, which should ideally be freely available, can still come at a high price.

Why do journals charge publication fees?

In reputable journals, articles undergo a process called peer review before publication. Experts in the field assess the work, identify weaknesses, suggest improvements, and decide whether it is ready to be published. This screening process helps ensure the quality and reliability of published research.

But, as the saying goes, there is no such thing as a free lunch. The process involves costs associated with editors, reviewers, and technical staff, as well as submission systems, plagiarism detection tools, typesetting, online publishing, unique identifiers such as DOIs, and digital archiving.

Many journals lack public or institutional funding, so they rely on APCs (Article Processing Charges), fees charged to authors to support the editorial process. In this model, authors are not paying for publication itself, but helping keep the journal running—at least in the best-case scenario.

Are there journals where you can publish for free?

Yes! There are high-quality, trustworthy scientific journals that are free both to read and to publish in.

These journals follow the open access publishing model, which allows anyone to read, download, and share articles free of charge, without paywalls or subscriptions.

One open access model stands out: diamond open access (💎), in which:

• The author does not pay to publish.
• The reader does not pay to access and read articles.
• The journal’s costs are covered through institutional support from universities, public bodies, or scholarly societies, which fund open access without passing the costs on to authors or readers.

Why isn’t every journal diamond open access?

Not every journal can operate under the diamond model because it requires ongoing institutional funding. That support is increasingly difficult to secure in countries facing repeated cuts to science funding, such as Brazil. As a result, many journals turn to author fees (APCs) to avoid having to close.

If diamond open access journals exist, why publish in journals that charge fees?

There is no simple answer, and it should not be used to diminish the diamond model, which is undoubtedly a fairer and much-needed path for science. Academic realities, however, do not always align with that ideal.

Many disciplines still have relatively few established diamond journals, particularly when international visibility is a priority. In some fields, the journals that perform best in academic assessment systems, such as Qualis or the Journal Impact Factor, are precisely those that charge fees. Maintaining quality and meeting indexing requirements can be both costly and administratively demanding.

Publishing in a journal that charges APCs can also be a strategic decision for researchers seeking visibility, stronger scores in funding or selection processes, or academic recognition, especially when the journal is well positioned in international indexing databases such as Scopus or Web of Science.

Watch out for predatory journals!

Not every free journal is a good one. Some charge hidden fees, promise rapid publication, and do not conduct genuine peer review.

Read our article “Predatory journals: what are they and how can you avoid them?” to avoid getting caught out.

How can you find diamond open access journals? Meet UNAM’s journal finder:

To help researchers who struggle to find scientific journals that publish without charging fees, the Universidad Nacional Autónoma de México (UNAM) developed the Buscador de Revistas Diamante. This journal finder makes it easier to identify journals that follow the diamond open access model.

Its straightforward interface lets you filter journals by title, ISSN, publisher, subject area and subfield, as well as region, country, and publication language. Search results indicate whether a journal is indexed in databases such as Scopus and Web of Science and show metrics such as CiteScore, Journal Impact Factor (JCR), and SJR when available. In some cases, the tool also shows the average time between submission and publication, which can help you choose a suitable journal.

1. Visit the official diamond journal finder website

Use the official link: https://digitalab-ssie.unam.mx/acuerdos/buscador_diamante

2. Understand the available filters

• Revista (Journal): Enter all or part of the journal’s title.
• ISSN: Enter the journal’s International Standard Serial Number (ISSN).
• Editor (Publisher): Select a publisher from the list.
• Categoría / Subcategoría (Category / Subcategory): Choose the journal’s subject area, such as medicine and health sciences.
• Región (Region): Select one or more geographical regions.
• País (Country): Select one or more countries.
• Idioma de publicación (Publication language): Choose the language or languages in which the journal publishes.

Please note: Journals that follow good editorial practices display their ISSN clearly on their website. If you cannot find it, you can check the ISSN Portal: https://portal.issn.org/.

3. Run a basic search

To get started, click the “Buscador” button.

Then scroll down a little to find the filters described in step 2.

Suppose you want to find journals in the health sciences.

First, open the Categoría dropdown and select Medicina y Ciencias de la Salud. Then click Buscar (Search).

The results show up to 15 journals per page. Click the green plus (+) icon to expand an entry and see more information about the journal.

4. Refine your search

You can also combine filters to narrow your search. For example:

• Categoría (Category): Medicine and health sciences
• País (Country): Brazil
• Idioma (Language): Portuguese

Then click Buscar to find journals that meet all three criteria.

If your search returns many results, use the “Filtrar por” field to enter specific terms that appear in the journal list, such as part of a journal’s title or publisher’s name, a country, or a category.

5. Start a new search

To clear all filters and start a new search, click Reiniciar (Reset).

6. Download the list as a CSV file

You can download the resulting journal list as a CSV spreadsheet by clicking the following button:

You can then analyze, filter, and organize the journals however you prefer, even offline.

7. A word of caution: not everything that sparkles is a diamond!

Take care when deciding where to submit your article. Some journals are listed as “diamond” open access but belong to commercial publishers that may charge indirect fees. The tool flags these cases with the warning “Editorial comercial” and highlights them in red in the results list.

You can also check the journals flagged in this way in the PDF list provided by UNAM: click here to view it.

8. Visit the journal’s official website

Click a journal’s title, shown in blue, to open its official website.

Read the information carefully to confirm the journal’s editorial policies and submission requirements.

Image source: Buscador de Revistas Diamante – UNAM