Encapsulated PostScript

EPS (Encapsulated PostScript) is a single illustration written in the PostScript language, made to be placed inside another document. Logos, stock vector graphics, charts for journals and artwork for sign makers, embroidery shops and printers still arrive as .eps. If a designer or a stock site gave you a logo “in vector format”, it was very likely EPS, often next to an AI and a PDF version.

Where EPS comes from

Adobe defined EPS in the late 1980s, when page layout programs needed a way to import graphics from illustration programs and print them sharply on PostScript printers. Version 3.0 of the specification, still the current one, was first released in 1990 and published as a separate document in 1992. EPS is publicly documented but owned by Adobe, and it has not been developed further. For most purposes PDF has taken over its role, yet EPS remains a common delivery format in stock graphics and scientific publishing.

What is in an EPS file

Technically, EPS is a PostScript program with restrictions: it may describe at most one page, must not change printer settings, and must declare its size. The header looks like this:

• %!PS-Adobe-3.0 EPSF-3.0 identifies the file,
• %%BoundingBox: 0 0 420 297 gives the rectangle the drawing occupies, in points (1/72 inch).

Thanks to the bounding box, the importing program knows how large the graphic is without running the PostScript code. Because programs in the 1980s could not render PostScript on screen, an EPS file often carries a separate preview: a TIFF or WMF image in a binary header on Windows (such files start with the bytes C5 D0 D3 C6), a PICT resource on old Macs, or an ASCII bitmap in the EPSI variant. Many applications show only this low-resolution preview, which is why an EPS can look blurry or show a grey box on screen and still print perfectly.

EPS can hold vectors, text with embedded fonts and raster images, in RGB, CMYK or spot colours. It cannot hold real transparency (it is flattened on export), layers, multiple pages, hyperlinks or fonts that are not embedded.

How to open EPS files

• Adobe Illustrator, CorelDRAW and Affinity Designer open and edit EPS; Photoshop opens it as a raster image.
• Inkscape (free, Windows, macOS, Linux) imports EPS through Ghostscript and lets you edit the paths.
• Windows: SumatraPDF with Ghostscript installed displays EPS. GIMP opens it as a bitmap at a resolution you choose.
• macOS: since macOS 13 Ventura, Preview no longer opens EPS (or PS). On older systems it converted EPS to PDF on the fly.
• Linux: Okular and Evince show EPS directly.

Common problems

EPS cannot be inserted into Word or PowerPoint

Microsoft turned off EPS support in Office for Windows with a security update in April 2017; Microsoft 365 and Office 2019 cannot insert EPS at all (Microsoft support article). Convert the EPS to PNG for a picture, or to EMF if you need a vector graphic that stays sharp when printed from Office.

EPS file won't open on Mac

That is the Ventura change mentioned above. Converting to PDF or SVG solves it, and both keep the graphic vector.

Low-quality or blank preview

You are seeing the embedded preview, not the actual drawing. A program that renders PostScript (Inkscape, Illustrator, Ghostscript-based viewers) shows the real content.

Colours look different after conversion

Print EPS files are often CMYK. Screen formats like PNG and SVG are RGB, so vivid CMYK greens and blues may shift a little.

Converting EPS

We do not use the preview; the PostScript code itself is rendered:

• EPS to PDF: the page is cropped to the bounding box, so the PDF is exactly as large as the graphic. Vectors and text stay vector.
• EPS to SVG: vector output for the web and Inkscape. Text becomes outlined shapes, so it looks right but is no longer editable as text.
• EPS to PNG at 150 dpi, EPS to JPG at 150 dpi with a white background and quality 90. For larger prints convert to PDF or SVG and scale there; see also SVG to PNG.
• EPS to EMF, WMF, DXF, ODG for Office, CAD and LibreOffice.

Facts

Further reading: EPS description at the Library of Congress.