Is 25 sources enough for my capstone literature review?

The short answer is that 25 sources is generally a very respectable baseline for an undergraduate capstone literature review, but you should absolutely prioritize the depth and relevance of your synthesis over hitting a specific target number. At 5,000 words, your current count of 22 to 25 peer-reviewed articles means you are averaging about one source per 200 words. This ratio is usually healthy because it allows you to actually analyze and connect the research rather than just listing summaries. Your advisor's request for a solid breadth of sources means they want to see that you have mapped the major debates and key players in your specific niche, not that you have simply compiled a massive bibliography. If your 22 sources thoroughly cover the foundational theories, the methodology trends, and the current debates of your topic, you are likely in a great position. A common misconception among senior students is that a longer reference list automatically equals a better grade. In reality, padding your bibliography with irrelevant papers just to hit a higher number usually backfires. It leads to superficial writing where you merely name-drop studies without critically evaluating them. For instance, imagine you are writing your capstone on how mindfulness apps affect academic anxiety in college students. If you have five high-quality, highly relevant papers detailing the exact cognitive mechanisms at play, that is infinitely better than citing fifteen different general studies about meditation that only tangentially relate to your specific population. The trade-off of searching for more sources this close to your deadline is that you risk losing precious time that would be better spent refining your writing, structuring your arguments, and ensuring your transitions are seamless. Your next steps really depend on the current structure of your draft and the specific sub-topics you are addressing. I highly recommend mapping your current sources against the main themes of your outline. If you find that one of your major sub-sections only relies on a single paper, that is a clear signal that you need to find two or three more articles to provide a balanced perspective. You should also look closely at your oldest sources; since you mentioned already trimming some older studies, make sure the classic, foundational papers of your topic are still represented alongside the cutting-edge research from the last five years. If your thematic map shows that every section has a balanced, diverse set of voices and your narrative flows logically from one point to the next, you can confidently stop searching for new papers and focus entirely on polishing your prose over these final three weeks.