Critical appraisal of evidence is performed to assess its validity, trustworthiness and usefulness in evidence-based practice. There currently exists a large number and variety of critical appraisal tools (also named risk of bias tools and quality assessment instruments), which makes it challenging to identify and choose an appropriate tool to use. We sought to develop an online inventory to inform librarians, practitioners, graduate students, and researchers about critical appraisal tools. This online inventory was developed from a literature review on critical appraisal tools and is kept up to date using a crowdsourcing collaborative web tool (eSRAP-DIY). To date, 40 tools have been added to the inventory (www.catevaluation.ca), and grouped according to five general categories: (a) quantitative studies, (b) qualitative studies, (c) mixed methods studies, (d) systematic reviews and (e) others. For each tool, a summary is provided with the following information: tool name, study designs, number of items, rating scale, validity, reliability, other information (such as existing websites or previous versions), and main references. Further studies are needed to test and improve the usability of the online inventory, and to find solutions to reduce to monitoring and update workload.