Theories, models, and frameworks (TMFs) are essential tools in dissemination and implementation (D&I) research, yet selecting and applying the most appropriate TMF is routinely a challenge, particularly for those new to the field. To address this need, we developed the Dissemination and Implementation Models in Health webtool (www.dissemination-implementation.org) a free, interactive, and evolving online resource designed to support the thoughtful use of D&I TMFs across all phases of research and practice – from planning through assessment. Created through a multi-institutional collaboration and refined using human-centered design, the webtool includes features such as logic model development, D&I TMF selection and comparison, guidance on combining and adapting models, strategies for application, and linkages to measurement tools. Since its initial release in 2014, the webtool has expanded to include over 110 D&I TMFs and new thematic content areas, including a section dedicated to health equity. It can be used in D&I trainings, proposal development, consultations, and academic coursework. Usage analytics and community feedback reflect ongoing relevance, utility, and evolving needs. The webtool continues to address a significant gap in D&I infrastructure by guiding users in selecting and operationalizing D&I TMFs, ultimately supporting more rigorous, context-sensitive translational research and practice.