What is the difference between AI and EPS files?
EPS files are older, larger and more flexible than AI files. AI files, on the other hand, are smaller, yet more detailed, than EPS files. If you want to manage your file sizes, AI may be your go-to file format. Many people consider AI files to be a streamlined and simplified subset of EPS files because of its vector-only support, easier editing capabilities and wide compatibility.
Originally, EPS files were more widely compatible than AI — but as software programs advanced and increased the number of files they were compatible with, AI files became the more accessible file type. The strong compatibility between the AI and PDF file types also meant they were easier to open than EPS.
History of EPS and AI.
Adobe Illustrator debuted in 1987 and quickly became a leader in graphic design software. In its early releases, Illustrator used EPS as its standard file format. It wasn’t until the release of Illustrator 9.0 that Adobe began to move away from the EPS file in favour of the PGF file, which later became the AI file.
Today, you can use either EPS or AI files to create both simple and complex drawings, illustrations, designs and more. However, because it’s the proprietary file format for Illustrator, most Adobe users still prefer AI.
Vector vs. bitmap.
A bitmap image is a map of pixels. Each pixel has its own colour, which — when combined in large groups — creates a large, detail-rich image. However, pixel-based images are difficult to scale because they consist of many individual pixels. When you scale a pixel-based image to a larger size than intended, it won’t have enough pixels to maintain picture quality at the new size.
Vector graphics use geometry and mathematical proportions — built on a system of points, lines, arcs, curves and polygons — to create images. They’re ideal for scaling because their foundational lines and shapes retain their ratios at any size.
EPS files can process both bitmap and vector images. AI files only handle vectors.
Complexity of image.
Many designers prefer to use the vector format for certain types of projects due to its precision, quality and scalability. You can scale vectors down to a business card size or up to the size of a billboard and get the same high-quality for both. AI files have the added benefit of being information-rich — they hold a lot of image data detail, making them easy to edit.
For artwork, AI files can handle more complex images than EPS files. A single page contains all its image data plus many different artboards, making the AI format easy to manipulate.
Another advantage of AI files is they support transparency. With layers, transparency helps graphic designers build artwork that they can use anywhere a design needs to seamlessly appear on top of various backgrounds, like a logo on a webpage.
The original use of EPS files was to embed images in websites and print advanced graphics. Today, JPEGs, GIFs and PNGs have replaced EPS for web use cases. However, EPS remains useful for printing — especially with images that contain complex graphics and high-resolution elements.
AI files are popular for small-scale graphics, especially for those with clean, sharp lines. Graphic designers often use them for logos, icons, posters and prints. Illustrator is also useful for typography design — creating fonts — and AI files are known for their ability to display fonts with precision.
AI files are becoming increasingly more commonplace than EPS. While people still use EPS files, designers and illustrators can just as easily create the same image types in AI files. As the default native format of Adobe Illustrator, AI files will only continue to grow in popularity.