Scientific figure DPI: check effective resolution, not metadata

The DPI number in the file is not enough

For raster artwork, the meaningful quantity is resolution at the size the figure will be reproduced. Pixel dimensions and intended publication width must be considered together.

Publishers use different targets for different artwork types

There is no universal rule that every scientific figure must simply be 300 DPI. Around 300 dpi is common for photographic or halftone images, while raster line art and combination artwork are often expected at substantially higher resolution.

Vector graphics are different

A vector PDF, EPS, or similar file does not have one intrinsic pixel resolution for its paths and text. Check whether vector elements remain vector, fonts are handled correctly, embedded raster images have enough effective resolution, and the journal accepts the chosen format.

Upsampling does not restore missing detail

Changing a low-resolution image from 150 to 300 in an export dialog, or interpolating it to twice as many pixels, does not recreate detail that was not present in the source. Re-export from the original plot or artwork when possible.

Source note

Publisher specifications are not universal and can change by journal, artwork type, and submission stage. The target journal’s current instructions remain authoritative.

• Elsevier — pixels, resolution, and print size
• Nature — photographic and vector artwork guidance
• IEEE — resolution and size