Figure Guide for Authors

For authors

Prepare high-quality figures for MDPI journals

Figures are a core part of your paper. Clear, sharp visuals help readers understand your results, support reuse in presentations and social media, and reduce delays at proof stage. This guide explains how to prepare figures that meet MDPI production standards.

View specifications Open the checklist Request figure editing help

Follow the specs

Use preferred formats, resolution, colour, and sizing so your figures reproduce cleanly in HTML and PDF.

Export carefully

Generate vector graphics where possible from the software you already use to create your plots and schemes.

Submit clearly

Place figures in the manuscript at the correct location, then optionally upload high-quality source files after acceptance.

Figure specifications

Technical requirements

Meeting these requirements helps production preserve the quality of your original artwork. When in doubt, prefer editable vector files over screenshots or compressed JPEGs.

File formats

  • Preferred (vector): PDF (vector), EPS, SVG, Adobe Illustrator (.ai)
  • Accepted (raster): TIFF or PNG at sufficient resolution
  • Use with care: JPEG only when no lossless source exists
  • Avoid: low-resolution screenshots pasted into Word

Resolution (raster)

  • Photographs / continuous tone: minimum 300 dpi at final print size
  • Line art, graphs, schemes: 600 dpi preferred (or provide as vector)
  • Combination figures: keep text and lines as vector when possible

Colour

  • Prepare figures in RGB for online publication
  • Use colourblind-safe palettes (see Accessibility)
  • Do not rely on colour alone to convey meaning; add labels, patterns, or shapes
  • Ensure adequate contrast between elements and background

Sizing

  • Design for single-column or double-column journal widths
  • Typical single-column width is about 8.5 cm; double-column about 17.5–18 cm (check your journal)
  • Keep fonts and symbols readable after reduction to final size
  • Do not submit unnecessarily oversized canvases that shrink text to illegibility

Fonts and line weights

  • Use a clear sans-serif font (e.g. Arial, Helvetica) embedded or outlined
  • Axis labels and panel letters typically 7–9 pt at final size
  • Minimum line weight about 0.5 pt at final size
  • Keep panel labels (a, b, c) consistent and placed outside the data area when possible

Multi-panel figures

  • Assemble panels into one composite figure when they share a caption
  • Align panels and use consistent style across the figure
  • Provide one source file for the composite; optional separate panels only if production requests them

Preparing figures by software

Export as vector wherever you can

Most plotting tools can export PDF, SVG, or EPS. Prefer those over copying a plot as a bitmap into PowerPoint or Word.

GraphPad Prism

Export graphs as PDF or EPS. Avoid copying as a bitmap. Check that fonts are embedded.

R / ggplot2

Use ggsave(..., device = cairo_pdf) or SVG. Set width/height in inches/cm to match journal columns.

Python / matplotlib

Save with plt.savefig("fig.pdf") or SVG. For raster, use DPI ≥300 and prefer PNG/TIFF over JPEG.

Excel

Charts often look soft when pasted. Copy to Illustrator/Inkscape or export via PDF print, then crop cleanly as vector.

Adobe Illustrator

Ideal for final assembly. Outline fonts if needed; export PDF/EPS/SVG. Keep editable master files.

Inkscape

Open-source vector editor. Save as PDF or SVG for submission of source figures after acceptance.

ChemDraw

Export structures as EPS/PDF or high-resolution TIFF. Keep bond and atom labels readable at final size.

Microscopy / imaging

Export TIFF from the acquisition software. Include scale bars in the image or as separate, clear overlays.

Accessibility

Make figures readable for more readers

Colour and contrast

  • Avoid red–green only distinctions; prefer colourblind-friendly palettes (e.g. blue/orange, viridis-style).
  • Check contrast between text and background.
  • Use patterns, shapes, or direct labels in addition to colour.

Captions and text alternatives

  • Write captions that explain what the figure shows, not only “see text”.
  • Define all abbreviations used in the figure.
  • Provide clear panel descriptions so readers who cannot see the image still follow the result.

Image integrity

Present data honestly and transparently

MDPI screens images for inappropriate manipulation. Follow journal ethics and good practice for western blots, gels, microscopy, and other image-based data. See mdpi.com/ethics and related integrity tools such as Proofig.

  • Do not enhance, obscure, move, remove, or introduce specific features.
  • Adjustments to brightness or contrast must be applied uniformly and disclosed when relevant.
  • Keep original unprocessed image files; you may be asked to provide them.
  • For spliced gels or composite images, clearly indicate boundaries and explain in the legend.
  • Never reuse images from other publications without permission and correct citation.

How to submit

Embed in the manuscript — then optionally upload sources

1

At submission and revision (required)

Insert each figure into your Word or LaTeX manuscript at the appropriate place in the text, with a caption. This remains the MDPI baseline and will not change. Peer review and layout placement depend on embedded figures.

2

After acceptance (optional, strongly encouraged)

When your paper is accepted, Susy will invite you to upload high-quality source figures (vector preferred). Map each file to the correct figure number (Figure 1, Figure 2, …). Suggested filenames: Figure_01.pdf, Figure_02.eps.

3

If you cannot provide better sources

Production will work from the manuscript. For low-resolution figures, MDPI may apply quality-improvement tools under human supervision. If you prefer professional preparation, MDPI Author Services offers figure and table editing.

Important: Optional source uploads do not replace embedded figures. Always keep figures in the manuscript at the correct location.

Pre-submission checklist

Before you submit

  • Figures are embedded in the manuscript at the correct places, with captions.
  • Vector formats used where possible (PDF/EPS/SVG); otherwise TIFF/PNG at ≥300 dpi (600 dpi for line art).
  • Text, symbols, and line weights remain readable at final journal column width.
  • Colour is colourblind-friendly; meaning does not depend on colour alone.
  • Panel labels (a, b, c) are consistent; abbreviations are defined in the caption.
  • Scale bars, units, and statistical annotations are clear and correct.
  • No inappropriate image manipulation; originals retained if requested.
  • After acceptance, high-quality source files are ready to upload (optional but recommended).

Optional support

Figure editing when you need a hand

Most authors can meet MDPI’s figure requirements with the guidance above. If preparing figures is taking too much time, or you want help with formatting, resolution, colour, or consistency across panels, MDPI Author Services can revise figures and tables to publication-ready standards.

View Author Services