One of the approaches followed by the circular economy (CE) to achieve sustainability through design is product life extension. Extending the life of products to make them useful for as long as possible is a means to reduce waste production and materials consumption, as well as the related impacts. For designers, conceptualizing products in a way that allows them to be used for longer is a challenge, and assessing how well they extend their lifespan can be helpful when it comes to choosing the best proposal. In this paper, 70 tools and methods related to eco‐design and circular economy are studied to determine how many of them consider parameters related to life extension and which can be applied in the early stages of design. The results of the analysis show that most of the existing tools and methods are applicable to developed products, and only a few of them take into account parameters related to extending the useful life. Of the 70 tools and methods, only 14 include some parameter related to life extension and are applicable to concepts. CE toolkit, Eco‐design PILOT, CE Designer, Circularity Assessment tool, Circularity Potential Indicator and Circular Design Tools take into consideration eight or more parameters to assess life extension in concepts. This will help designers select the most appropriate and will indicate the need for more complete tools to consider useful life extension in the early stages of design and thus enhance the selection of more sustainable products.

Consumers are showing a growing concern for the environment and sustainability, while they keep their interest in more creative products that ‘delight’ them and exceed their expectations. Consequently, designers must meet the circular economy (CE) requirements, but also provide creative solutions. The present research describes an experiment in which a group of designers were asked to solve design problems using two different methods: random stimuli and biomimicry. The results help to answer the question regarding whether methods focused on requirements (biological requirements in this case) are as effective for obtaining creative solutions as methods oriented toward creative ideas (specifically random stimuli). The paper also examines whether biomimicry stimuli promote circularity to a sufficiently greater extent than a random stimulus to compensate for the possible loss of creativity with respect to the random method. The results show that biomimicry stimuli promote circularity in the concepts without diminishing their creativity.