Background: Fermented foods vary significantly by food substrate and regional consumption patterns. While consumed worldwide, their consumption and potential health benefits remain understudied. Europe, in particular, lacks specific consumption recommendations for most fermented foods. Objective: This project, which is under the framework of the PIMENTO COST Action (CA20128), aims to develop a validated tool to quantitatively estimate fermented food intake across European Regions. Methods: Fermented foods were categorized into broad groups (e.g., dairy, plant-based, meat, beverages) based on product classifications, ensuring that the foods included were genuinely fermented through ingredient analysis. Participants aged 18+ were recruited online via snowball sampling. They were asked to provide informed consent and agree to data collection under ethical guidelines using a GDPR-compliant platform. Results: A representative sample of 1536 participants per European region was targeted, ensuring diversity in age and sex, with the goal of achieving a 60% response rate. A multilingual questionnaire was developed and pilot-tested for clarity. The upcoming steps will include final validation for accuracy and repeatability using 24-hour dietary recalls and specific statistical techniques of analysis to ensure reliability. Conclusions: The validated online-based Fermented Foods Frequency Questionnaire (3FQ) aims to address current gaps in fermented food intakes to help improve future research in this important area.