When crafting a scientific paper, poster, or PowerPoint presentation, the thought of creating the necessary images can be daunting after extensive writing. Clear and precise visuals are crucial in scientific communication, but did you know that you can alleviate this burden by using free professional clipart and stock photos? 

Here, we introduce several free image resources with tons of scientific clipart and elements perfect for enhancing your publication. However, remember to check the journal’s policy on third-party content, as some journals require all images to be created by the authors themselves, prohibiting any online material, even from the public domain.

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1. Servier Medical Art

Best For: High quality illustrations useful for graphical abstracts and presentations

Servier Medical Art is a very comprehensive resource that offers a vast collection of free medical illustrations and clip art. Created by Servier, a global pharmaceutical company, this platform provides high-quality, professionally drawn images covering a wide range of medical as well as biological topics. The images can be downloaded in various formats including PNG and PPTX, and tutorials are also available on their website showing how you can use them in different ways.

These illustrations are available under a Creative Commons Attribution 4.0 Unported License, which means they can be used freely in educational materials, presentations, and publications, provided that proper attribution is given, making it an invaluable tool for students, and professionals alike.

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2. Bioicons

Best For: Icons on topics like biochemistry, immunology, and oncology, with extensions for Draw.io and InkScape

Bioicons is an online resource offering a collection of free, high-quality scientific icons and illustrations covering different topics of biology. These icons are designed to be visually appealing, making them perfect for use in research presentations, posters, and publications. You can easily copy the icons directly from the website to your clipboard and paste them wherever needed.

Bioicons are available under a Creative Commons license, which allows for free use with proper attribution.

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3. VectorStock

Best For: Scalable illustrations and clipart suitable for abstracts and presentations

VectorStock offers a vast collection of vector graphics, including scientific and technical illustrations, icons, and clipart. It provides both free and premium vectors, making it a valuable resource for various professional and personal projects. The vector images can be downloaded as PNGs and scaled without losing quality and can enhance the clarity and professionalism of PowerPoint presentations, posters, making the scientific data more comprehensible and visually appealing.

Many vectors on VectorStock are free and often require attribution. The vast selection of premium vectors can be purchased for a certain amount of fee, and usually come with more flexible licensing options.

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4. Pixabay

Best For: Vector graphics and illustrations on a wide range of subjects

Pixabay is a popular online platform with a vast and diverse collection of free images, vector graphics, illustrations, and even videos. The high quality images and illustrations from Pixabay can be downloaded as PNG or SVG files, and cover a huge range of topics, from nature to arts and architecture. You can use them in research presentations, publications, graphical abstracts, as well as educational materials to create clear and informative content.

The best part is that all content on Pixabay is free to use and released under the Pixabay License, which allows free use for both personal and commercial purposes without requiring attribution, although credit to the creator is appreciated.

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5. Openclipart

Best For: Technical illustrations and diagrams with a user-friendly interface

Openclipart is another platform that offers a huge library of free, high-quality clipart images including specific scientific and technical illustrations. 17,000+ clipart are available on different themes, from health and wellness to geology. The site is community-driven, with artists from around the world sharing and contributing their work. The platform is very user-friendly, allowing for quick searching and downloading of images in various formats including PNG and SVG.

All images on Openclipart are released into the public domain, meaning they can be used freely without any restrictions.

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6. Unsplash

Best For: Different types of stock images like 3D render, textures, and photographs

Unsplash is among the very popular resources that has a massive collection of high-resolution, free-to-use images. It also features different types of images like 3D render, textures, etc. The pictures can be very helpful in presenting scientific data in a visually engaging manner.

The photos on Unsplash are released under the Unsplash License, which allows for free usage for personal and commercial purposes. Attribution is not needed and acknowledging the photographer is encouraged. 

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7. SciDraw

Best For: Vectors graphics mostly covering biosciences, available in SVG and PNG

SciDraw is an online repository of high-quality illustrations, designed specifically for the scientific community, and provides detailed images covering a wide range of scientific disciplines, including biology, chemistry, physical, and environmental science among others. The vectors can be downloaded in SVG format.

The rich resources at SciDraw are offered under various Creative Commons licenses, allowing for flexible use while requiring proper attribution and adherence to specific terms. 

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8. Clker

Best For: Diverse clipart in various sizes, specifically designed for scientists

Clker serves as a valuable resource for scientists seeking to enhance the visual appeal and clarity of their work. All clipart on Clker is free to use and easily downloadable in various sizes, making it a cost-effective solution for scientists working with limited budgets.

It should be noted that clipart designated as public domain on Clker can be used freely for any purpose without restrictions. However, some clipart on Clker may be offered under Creative Commons licenses, such as CC0 (public domain dedication) or CC BY (attribution). It is suggested to the users to review the specific license associated with the images of their choice to understand the usage rights and any attribution requirements.

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9. Vecteezy

Best For: Graphics useful in scientific presentations

Vecteezy is another indispensable resource for scientists aiming to elevate the visual appeal and clarity of their scientific communications. Boosting a vast library of free vector graphics, the diverse range of visuals are suitable for all types of scientific content. 

The licensing agreement on Vecteezy specifies that most content is available under a standard license, allowing for personal and commercial use with attribution. Some premium content may have additional restrictions, and users are encouraged to review each asset’s specific licensing terms before use.

 

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