The general Frontiers author guide does not define one standalone graphical abstract specification. Check the exact journal page and current figure rules.
Elsevier recommends a minimum 1328 × 531 px graphical abstract at 300 dpi. Check the current preferred formats and your journal-specific instructions.
Cell Press published a 1200-pixel-square graphical-abstract guide in 2018. Treat it as an official reference and verify the live journal instructions.
ACS TOC-graphic requirements vary by journal. Use ACS Catalysis as a current cited example, then verify the exact title and article type.
Graphical-abstract size, resolution, color, and file rules are journal-specific. Compare cited examples, then verify the exact journal.
Build a graphical abstract in PowerPoint, export an image, and verify its pixel dimensions and file type against the exact journal instructions.