Diamond Open Access Journals

• Diamond open access journals are scholarly publications that charge no fees to authors or readers, relying on third-party funding and volunteer labor.
• They typically publish 15–34 articles per year with low operational costs, utilizing automated workflows and community-driven support.
• Key challenges include limited indexing, funding instability, and volunteer burnout, driving policy and structural reforms for enhanced sustainability.

Diamond open access (OA) journals are scholarly journals that charge neither authors nor readers at any point in the publication process. They contrast with gold OA (author-pays, free to read), green OA (reader access via self-archived versions), and hybrid OA models. Diamond OA's core premise is that all funding for editorial tasks, platform operation, and dissemination arises from third parties—universities, libraries, learned societies, or government grants—without levying article processing charges (APCs) or subscription fees. This configuration is widely regarded as the idealized, most equitable end-state for academic publishing in current science policy debates, but its practical realization and long-term sustainability are conditioned by a complex interplay of institutional support, workflow design, team structures, disciplinary context, and indexing practices (Taubert, 28 Nov 2025).

1. Formal Definitions and Distinguishing Features

The essential defining criteria for diamond OA are universal free access (no subscription fees) and complete absence of APCs for authors. The minimal operationalization is: $$F_{\min} = \{\text{no subscription fees for readers},\; \text{no APCs for authors}\}$$ Additional widely cited criteria include presence of peer review, permanent identifiers (DOI/ISSN), publication under open licenses (often CC BY), and stewardship by non-commercial, community-driven entities (Taubert, 28 Nov 2025).

Key contrasts:

• Gold OA: All articles open to readers, but publishers levy APCs on authors or their funders.
• Hybrid OA: Subscription journals with optional APCs to un-paywall specific articles.
• Green OA: Authors self-archive, but the version of record typically remains behind paywalls.
• Diamond OA: No charges to either side; operational expenses are covered by consortia, institutions, or other public/non-profit means (Taubert, 28 Nov 2025, Pierantonio et al., 2020, Kontorovich, 6 Jan 2026, Bellen et al., 2024, Sugita, 14 Nov 2025).

Table 1: Comparative features of principal OA models

Model	Reader Fees	Author APCs	Typical Funder
Subscription	Yes	No	Libraries/individuals
Green OA	No (preprint/postprint)	No	N/A (via self-archiving)
Gold OA	No	Yes	Authors/funding agencies
Hybrid OA	Sometimes	Optional	Mixed
Diamond OA	No	No	Institutions, societies, grants

2. Quantitative Landscape: Scope, Scale, and Publication Output

Recent global estimates place the number of active diamond OA journals in the range of 17,000–29,000, representing approximately two-thirds to three-quarters of all gold-classified OA journals; however, only about 30% of the total OA article output occurs in diamond journals (Taubert, 28 Nov 2025). Disciplinary and regional diversity are pronounced: 61% of diamond OA titles are in social sciences and humanities (SSH), with significant representation in Latin America, southern/eastern Europe, and Asia (Simard et al., 2024, Taubert, 28 Nov 2025). In Canada, 62% of active scholarly journals are diamond OA, with 85% of all new journals founded since 2015 following this model (Bellen et al., 2024). Germany reports 298 active diamond OA scientific journals, mostly within SSH (72.5%) (Taubert et al., 2023).

Typical annual output per diamond OA journal is modest: DOAJ-listed diamond OA titles average 34 articles/year, with national medians of 15–16/year in Switzerland and Germany, compared to 72/year for typical Web of Science-indexed titles (Taubert, 28 Nov 2025, Taubert et al., 2023). Mega-journals (high-volume, multidisciplinary) are virtually absent from diamond OA.

3. Operational Models, Cost Structures, and Workflow Automation

Diamond OA journals are financed through pooled institutional or grant funding, volunteer labor, and, in some professionalized cases, consortial or governmental support. Many operate on annual budgets under €10,000 (Bosman et al. 2021a), with at least a quarter managing with less than €1,000. Cost structures usually include fixed expenses (DOI registration, hosting, archiving) and variable marginal costs (limited to copy-editing or DOI assignment) (Taubert, 28 Nov 2025, Bos et al., 14 Apr 2025). A generalized formula is: $C = c_f + c_v n$ where $c_f$ is annual fixed cost, $c_v$ is per-article variable cost, and $n$ is articles/year. Highly automated, LaTeX-centric workflows have demonstrated feasible annual outlays as low as \$705 + \$1/article in mathematics, assuming heavy author-side typesetting and technical volunteer input (Bos et al., 14 Apr 2025).

Exemplars:

• The Association for Mathematical Research (AMR) operates journals at ≈\$3,000/year with per-article costs scaling approximately as \( C=\frac{3,000}{N} \), with N=60 yielding \$50/article (Kontorovich, 6 Jan 2026).
• The Journal of Object Technology’s diamond OA model covers expenses (<€2,000/yr) exclusively through institutional sponsorship and in-kind volunteer labor (Pierantonio et al., 2020).
• Canadian SSH journals often benefit from provincial and national consortia (e.g., Érudit), with pooled library funding subsidizing infrastructure and editorial work (Bellen et al., 2024).

Table 2: Representative annual cost structures (as reported)

System/Journal	Fixed Cost (€/yr or $$/yr)</th> <th>Variable Cost (per article)</th> <th>Typical Output/year</th> </tr> </thead><tbody><tr> <td>AMR experiment</td> <td>$$3,000	Negligible	60
LaTeX/HotCRP workflow	$705 |$1	100–1,000+
JOT (Platinum OA)	€2,000	0	40

In almost all systems, editorial labor (peer review, copy-editing) is performed by academics or students, often uncompensated, which survey data identify as a potential long-term vulnerability (Taubert, 28 Nov 2025, Taubert et al., 2023).

4. Disciplinary, Geographic, and Linguistic Diversity

Diamond OA journals predominate in SSH fields: more than 70% in Germany and 70–75% in Canada’s SSH domains (Taubert et al., 2023, Bellen et al., 2024). By contrast, natural sciences and engineering are under-represented. Language variety is a hallmark: about one-third of diamond OA titles accept multiple languages (vs. <15% among APC journals), and only 70.5% publish in English; substantial shares use Spanish (25.7%), Portuguese (17.4%), or French (9.1%) (Taubert, 28 Nov 2025, Simard et al., 2024). Non-English and multilingual journals are particularly prevalent in Latin America and Europe, and especially so in SSH (Simard et al., 2024).

Regionally, diamond OA’s publisher base is highly decentralized: universities account for over 70% globally, with not-for-profits, scholarly societies, and state agencies supplementing; commercial involvement is limited (≈3–17%, depending on country) (Taubert, 28 Nov 2025, Taubert et al., 2023). In Canada and Latin America, shared infrastructure (e.g., OJS, Érudit, SciELO, Redalyc) furthers local journal diversity and bibliodiversity (Bellen et al., 2024, Taubert, 28 Nov 2025).

5. Indexing, Discoverability, and Visibility

Coverage of diamond OA journals in major bibliometric databases (WoS, Scopus) remains low. Simard et al. report that only 32% of DOAJ-listed diamond OA journals are present in WoS, and 38% in Scopus; for SSH diamond OA journals, coverage drops to 32% (Simard et al., 2024). Gold OA journals have much higher representation (BM: 77%, NSE: 68%). Language and geography drive indexation bias: English-only journals are much more likely to be indexed, and journals from high-income countries dominate indexed sets (Simard et al., 2024, Taubert, 28 Nov 2025). OpenAlex, as a newer infrastructure, covers over 90% of DOAJ benchmarks.

The lack of comprehensive indexing affects assessment, citation analysis, and tenure/grant evaluation, perpetuating a bias against multilingual, regional, or non-commercial titles. Policy recommendations highlight the need for expanded coverage and the use of alternative databases (DOAJ, OpenAlex) for research assessment and compliance monitoring (Simard et al., 2024, Taubert, 28 Nov 2025, Bellen et al., 2024).

6. Governance, Sustainability, and Structural Challenges

Long-term sustainability is a persistent concern. Case studies identify gift-based volunteer labor as the linchpin—but also the primary point of fragility (Taubert et al., 2023, Taubert, 28 Nov 2025). The key structural vulnerabilities are:

• Volunteer burnout: Overload and lack of succession lead to journal discontinuation (e.g., 23 German diamond OA journals ceased due to loss of key actors or grant expiry) (Taubert et al., 2023).
• Funding instability: Time-limited grants, insufficient institutional baseline support, and the absence of permanent editorial staff threaten continuity (Taubert et al., 2023, Bellen et al., 2024).
• Limited task division: Small editorial teams often multitask, hampering scalability and resilience (Taubert et al., 2023).
• Indexing and “invisibility”: Low inclusion in major databases can affect journal sustainability via reduced submissions and institutional prestige (Taubert, 28 Nov 2025, Bellen et al., 2024).

Landscape analyses propose mapping journals by team size and degree of monetization of editorial tasks. Sustainable models generally combine diversified institutional funding, stable consortial support, platform-based efficiencies, and rotation of volunteer responsibilities (Taubert et al., 2023, Taubert, 28 Nov 2025, Pierantonio et al., 2020). Policy guidance stresses:

• Multi-year operating grants, especially for new or small journals (Bellen et al., 2024)
• Professionalization of critical roles (editorial production, technical maintenance)
• Upskilling volunteers and ensuring knowledge transfer for succession

7. Policy, Normativity, and Future Research Priorities

Diamond OA lies at the intersection of scholarly, institutional, and policy logics. Science policy documents since 2020, particularly in Europe, have advanced diamond OA as the “most equitable” model, tying it to goals of bibliodiversity, inclusion, and public-good knowledge production (Taubert, 28 Nov 2025). However, many empirical studies critique the normative bias in policy-aligned research, calling for more systematic evaluations of labor dynamics, funding models, and the full opportunity cost of uncompensated editorial service.

Outstanding research gaps include:

• Disciplinary asymmetries (the persistent SSH tilt)
• Capacity for scaling beyond small-to-medium outputs
• Mechanistic studies on journal discontinuation and editorial team demography
• Comparative cost accounting—including in-kind, opportunity, and explicitly paid labor
• Efficacy and limits of policy interventions for sustainable, inclusive diamond OA ecosystems (Taubert, 28 Nov 2025)

A plausible implication is that the sustainability and diversity of the diamond OA landscape depends less on ideology and more on the orchestration of robust infrastructure, policy alignment (particularly regarding assessment practices), and adaptive governance attuned to local and disciplinary realities.

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References

• (Pierantonio et al., 2020) Pierantonio et al., "Open Access all you wanted to know and never dared to ask"
• (Shashok, 2017) Neylon, "Can scientists and their institutions become their own open access publishers?"
• (Simard et al., 2024) Simard et al., "The open access coverage of OpenAlex, Scopus and Web of Science"
• (Bos et al., 14 Apr 2025) Boneh et al., "Lowering the Cost of Diamond Open Access Journals"
• (Kontorovich, 6 Jan 2026) Association for Mathematical Research, "Diamond Open Access: The AMR Experiment"
• (Sugita, 14 Nov 2025) Sugita, "The current state of open access"
• (Bellen et al., 2024) Gagnon et al., "Diamond open access and open infrastructures have shaped the Canadian scholarly journal landscape since the start of the digital era"
• (Taubert, 28 Nov 2025) Taubert, "Research on Diamond Open Access in the Long Shadow of Science Policy"
• (Taubert et al., 2023) Taubert et al., "Mapping the German Diamond Open Access Journal Landscape"