PNAS Impact Factor, Submission Tracks and Figure Requirements

PNAS, the Proceedings of the National Academy of Sciences of the United States of America, has been the flagship journal of the US National Academy of Sciences since 1914. It spans the biological, physical and social sciences, publishes more than 3,500 research papers a year and draws over 5 million page views a month. Articles are published daily and collected into weekly issues.

PNAS works differently from most journals in two ways that shape a submission: it has two routes in (Direct Submission for everyone, Contributed Submission for Academy members), and it measures length in printed pages rather than words alone. This guide covers both, along with the impact factor, the acceptance rate, the fees, the figure specifications and a checklist. Everything comes from PNAS's own pages and its publisher's pages for PNAS Nexus, listed under Sources. The pnas.org pages were read on 8 November 2026 from their latest archived copies, and each is dated in the Sources.

PNAS impact factor

The most recent metrics we could confirm on pnas.org are PNAS's 2024 metrics:

The 2023 column comes from PNAS's journal metrics page, which also listed an impact factor without self-citations of 9.2 and a rank of 13th of 134 journals in Multidisciplinary Sciences. The 2025 values from Clarivate's June 2026 release were not on the PNAS pages we could access; the PNAS article and journal metrics page, linked below, is where they will appear.

An impact factor is an average over every paper a journal publishes, and PNAS publishes more than 3,500 research papers a year across the physical, biological and social sciences. Compare it with the journals in your own discipline rather than with the headline numbers of other general journals.

PNAS or PNAS Nexus? They are different journals. PNAS Nexus has its own pages on Oxford Academic, which list a 2025 impact factor of 4.8 and a 2025 CiteScore of 6.7. If a figure you have seen for "PNAS" looks low, check which journal it belongs to. In reference lists, PNAS is abbreviated Proc. Natl. Acad. Sci. U.S.A., the form PNAS itself uses.

Is PNAS a good journal? Acceptance rate and timeline

PNAS's editorial policies give its acceptance rate as 14% and say that more than half of submissions are declined at initial evaluation. It receives more than 18,000 Direct Submissions a year, and they make up more than 75% of the research it publishes.

PNAS's published timing figures:

• 2023 metrics page: the Editorial Board's initial decision to decline without review took 13 days on average; a full review took 47 days on average; and submission to issue publication averaged 6.6 months. The acceptance rate for Direct Submissions in 2023 was 14.7%.
• 2025 Author Center: a full review takes 45 days on average, and most articles publish within six months of submission.
• After acceptance: PNAS says it can publish in as little as 4 to 5 weeks.

Direct Submissions get single-anonymous peer review: reviewers know who the authors are, but the authors are not told who the reviewers are.

Direct Submission and Contributed Submission

A paper rejected as a Direct Submission cannot be resubmitted as a Contributed one, and Brief Reports cannot be contributed. Newly elected members may also submit an Inaugural Article within five years of election.

PNAS article types and length limits

PNAS counts length in published pages.

The front matter has its own limits:

• Title: under 135 characters.
• Abstract: no more than 250 words.
• Significance Statement: 50 to 120 words, with no references, written so that an undergraduate-educated scientist outside the field can follow it. It is required for Direct and Contributed Submissions. Treat it as the paper's case for general interest, because that is how editors use it.
• Keywords: at least three. The templates say three to five.

Sections and classifications

Every paper is classified into one of three sections and a classification within it. Dual classifications are permitted between major categories, for example Biophysics and Computational Biology in the Biological and the Physical Sciences.

• Physical Sciences: Applied Mathematics; Applied Physical Sciences; Astronomy; Biophysics and Computational Biology; Chemistry; Computer Sciences; Earth, Atmospheric, and Planetary Sciences; Engineering; Environmental Sciences; Mathematics; Physics; Statistics; Sustainability Science.
• Social Sciences: Anthropology; Demography; Economic Sciences; Environmental Sciences; Political Sciences; Psychological and Cognitive Sciences; Social Sciences; Sustainability Science.
• Biological Sciences: Agricultural Sciences; Anthropology; Applied Biological Sciences; Biochemistry; Biophysics and Computational Biology; Cell Biology; Developmental Biology; Ecology; Environmental Sciences; Evolution; Genetics; Immunology and Inflammation; Medical Sciences; Microbiology; Neuroscience; Pharmacology; Physiology; Plant Biology; Population Biology; Psychological and Cognitive Sciences; Sustainability Science; Systems Biology.

How to submit to PNAS

1. No presubmission inquiry. PNAS does not consider them, except proposals for Perspectives.
2. Prepare the manuscript. Initial submissions are format-neutral, but the file must include a title page, abstract, Significance Statement and data sharing plans. PNAS offers Word templates for Research Reports, Brief Reports and the SI Appendix (updated August 2025), and a LaTeX template on Overleaf. The submission system runs PDFLaTeX and uses the pnas-new.bst bibliography style.
3. List possible editors and reviewers. Name appropriate Editorial Board members, NAS members and qualified reviewers, at least three of each.
4. Add your ORCID. The corresponding author must supply an ORCID identifier in the submission system, not in the manuscript file.
5. Disclose any preprint. Posting on servers such as arXiv or bioRxiv is permitted and does not affect consideration, but it must be disclosed.
6. Enter competing interests directly into the submission system, covering the 48 months before submission.
7. Submit through PNAS Central.

PNAS's author pages do not set out what a cover letter must contain; the Significance Statement does most of that job. If you are asked to revise, the revised paper is due within two months of the decision.

PNAS publication fees and open access

PNAS is a hybrid journal. These charges apply to articles published in volume 123 and later.

Under either option, every PNAS article is free to read within six months of publication. PNAS grants waivers to authors without funding to cover the charges, for example in mathematics and astronomy or from lower-income countries. Several institutional agreements change the price: UK authors under the Jisc agreement (1 January 2026 to 31 December 2027) and Max Planck authors (1 May 2026 to 30 April 2029) publish open access without paying an APC, and the University of California agreement sets a discounted rate of $3,355 per article. Authors may also deposit their accepted manuscript immediately upon publication.

PNAS figure requirements

PNAS's digital art guidelines give exact sizes and resolutions. All values apply at publication size.

The submission page adds a few practical points:

• Formats: it also lists PPT as acceptable, although the digital art guidelines advise against Microsoft Office files.
• Text: it caps text at 12 pt after reduction.
• Display sizes: it describes three typical sizes, about 9 × 6 cm (small), 11 × 11 cm (medium) and 18 × 22 cm (large).
• Final size: provide every image at final size, with composite figures already assembled.
• 3D images: PRC or U3D format.

Two numbers are easy to overlook. Article PDFs display images at 200 ppi and the HTML version at 300 ppi, so detail finer than that is lost online. And a combination figure, with a photograph plus labels or a chart, needs 600 ppi or more, not 300. At 8.7 cm that means at least 2,055 pixels across. The image DPI checker has the PNAS widths as presets and shows the pixel count each resolution needs. Journal figure requirements by publisher puts PNAS next to 13 other publishers.

Figure legends and statistics

PNAS is specific about what a legend must say:

• Label error bars clearly in every graph and define them in the legend.
• State whether a number after ± is a standard error of the mean or a standard deviation.
• Give the number of independent data points (N).
• Start numerical axes at zero, except for log axes.
• Show statistics and error bars only for independent experiments, not for replicates within one experiment.

The figure legend generator has fields for each of these, so none is left out.

Image integrity and AI

No specific feature in an image may be enhanced, obscured, moved, removed or introduced. Images grouped from different sources must be shown as grouped. Brightness, contrast or colour balance changes are acceptable only when applied to the whole image. PNAS screens images and refers questions to the editors.

PNAS does not allow AI tools to create images or graphics unless the software is itself the subject of the paper, and any AI use in the research must be disclosed in the Methods (or Acknowledgments) with the tool's name and version. Cover art submissions (21.59 × 27.94 cm, EPS or TIFF) are not considered if they are AI-generated or stock images.

References and style

• References follow PNAS style, numbered in the order they appear in the text.
• With more than five authors, list the first author followed by "et al."
• Abbreviate journal titles as in MEDLINE/PubMed, for example: Proc. Natl. Acad. Sci. U.S.A. 88, 10362–10366 (1991).
• "Data not shown" is not permitted.
• PNAS follows the CSE Manual (Scientific Style and Format, 8th edition) and SI units.
• Do not include statements of novelty or priority.

Data, code and reporting policies

• Data and code: all materials, data, protocols, code and scripts used in the analysis must be in a public repository on publication, and datasets must be cited in the references.
• Reporting: follow your field's reporting standards from the EQUATOR Network, and ARRIVE for animal studies.
• Clinical trials: register them in an accepted registry before enrolment begins, following ICMJE policy.

Pre-submission checklist for PNAS

• Right journal (PNAS, not PNAS Nexus), right section and classification, and right track (Direct, Contributed or Brief Report).
• Length within 6 pages (about 4,000 words, 50 references, 4 medium display items), or 3 pages and 15 references for a Brief Report.
• Title under 135 characters, abstract 250 words or fewer, and Significance Statement of 50 to 120 words with no references.
• At least three keywords.
• Title page and data sharing plan in the file.
• At least three suggested Editorial Board members, three NAS members and three reviewers.
• Corresponding author's ORCID ready, and any preprint disclosed.
• Competing interests for the past 48 months entered.
• Figures built at 8.7, 11.4 or 17.8 cm wide and no taller than 22.5 cm.
• Text at least 6 pt in an approved font, lines at least 0.25 pt and fonts embedded.
• Photographs at 300 ppi or more, combination figures at 600 ppi or more and line art at 1000 ppi or more, in RGB TIFF, EPS or PDF.
• Error bars defined, ± values identified as SEM or SD, N given and axes starting at zero.
• Colours readable by colour-blind readers, checked in the colorblind simulator.
• No AI-generated images, and only whole-image adjustments.
• Data, code and protocols ready for a public repository.
• Delayed or immediate open access chosen, and any institutional agreement or waiver checked.

Related guides and tools

Our journal submission figure checklist covers the checks every journal shares. If you are deciding between general journals, see our guides to Nature, Science Advances, Nature Communications and eLife; medical researchers should also read the JAMA guide.

Because PNAS does not accept AI-generated images in papers or as cover art, use the graphical abstract maker and journal cover maker only for talks, posters and social posts, and draw anything you submit yourself.

Sources

PNAS pages were read on 8 November 2026 from the most recent archived copy of each official page; the date of that copy is given in brackets.

• PNAS: Submitting your manuscript (17 June 2026; article types, front matter, classifications, submission, figures, legends, references)
• PNAS: Editorial and journal policies (31 July 2026; acceptance rate, peer review, preprints, image integrity, data, AI)
• PNAS: Publication charges (12 June 2026; fees, licences, waivers, agreements)
• PNAS: Article and journal metrics (25 July 2025; 2023 metrics and timings)
• PNAS: Author Center (7 October 2025; 2024 metrics, review time)
• PNAS: About (16 November 2025; history, scope, output, submissions)
• PNAS: Member-contributed submissions (31 March 2025)
• PNAS digital art guidelines (PDF) (live; updated 16 February 2022)
• PNAS Nexus: About (live; PNAS Nexus 2025 impact factor and CiteScore)