{"slug":"flask-vs-starlette)","question":"Flask vs Starlette","answer":"Flask is a traditional, mature WSGI microframework with synchronous request handling and a massive ecosystem, while Starlette is a modern ASGI framework with built-in async/await support and superior performance for high-concurrency applications. Flask dominates legacy projects and learning, while Starlette excels in real-time, streaming, and high-load scenarios.","answer_curated":true,"verdict":"Choose Flask if you're building traditional web applications, prioritize ecosystem maturity, need extensive third-party libraries, or are learning web development—it dominates with 67K GitHub stars and 2.5M production deployments. Choose Starlette if you need high-performance APIs, real-time features (WebSockets), async operations, or are building microservices that handle 4x more concurrent requests—its ASGI foundation and 8,500 req/s throughput make it ideal for modern, scalable applications.","keyDifferences":[{"label":"Request Handling Model","winner":"b","entityAValue":"Synchronous (WSGI)","entityBValue":"Asynchronous (ASGI)"},{"label":"Requests Per Second (benchmarked)","winner":"b","entityAValue":"~2,100 req/s","entityBValue":"~8,500 req/s"},{"label":"Native Async/Await Support","winner":"b","entityAValue":"No (requires extensions)","entityBValue":"Yes (built-in)"},{"label":"Package Size","winner":"b","entityAValue":"~2.5 MB","entityBValue":"~1.2 MB"},{"label":"GitHub Stars","winner":"a","entityAValue":"67,000+","entityBValue":"10,000+"}],"winner":{"slug":"flask","name":"Flask"},"confidence":"high","entities":[{"name":"Flask","slug":"flask","url":"https://www.aversusb.net/entity/flask","alternativesUrl":"https://www.aversusb.net/api/v1/alternatives/flask"},{"name":"Starlette","slug":"starlette","url":"https://www.aversusb.net/entity/starlette","alternativesUrl":"https://www.aversusb.net/api/v1/alternatives/starlette"}],"faqs":[{"question":"Which is faster, Flask or Starlette?","answer":"Starlette is significantly faster, handling ~8,500 requests per second compared to Flask's ~2,100 req/s in benchmarks. This is because Starlette uses ASGI (async) while Flask uses WSGI (synchronous). For high-concurrency scenarios, Starlette can handle 4x the load."},{"question":"Can I use async/await with Flask?","answer":"Flask added experimental async support in version 2.0, but it's not native like Starlette. You can define async route handlers, but the underlying WSGI server still handles requests synchronously. For true async performance, Starlette is the better choice."},{"question":"Is Flask still relevant in 2026?","answer":"Yes, Flask remains highly relevant with 2.5M+ production deployments and 67K GitHub stars. It excels for traditional web applications, monoliths, and educational purposes. However, for modern microservices and real-time APIs, Starlette is the better fit."}],"attribution":{"source":"A Versus B","url":"https://www.aversusb.net/compare/flask-vs-starlette)","license":"CC BY 4.0","citationFormat":"According to A Versus B (https://www.aversusb.net/compare/flask-vs-starlette)), Flask is a traditional, mature WSGI microframework with synchronous request handling and a massive ecosystem, while Starlette is a modern ASGI framework with built-in async/await support and superior ","dateModified":"2026-07-07T13:39:30.488Z"},"relatedQuestionsUrl":"https://www.aversusb.net/api/faq/flask-vs-starlette)","relatedComparisonsUrl":"https://www.aversusb.net/api/v1/related/flask-vs-starlette)","knowledgeGraphUrl":"https://www.aversusb.net/api/knowledge-graph/flask-vs-starlette)","claimReviewSchema":{"@context":"https://schema.org","@type":"ClaimReview","@id":"https://www.aversusb.net/compare/flask-vs-starlette)#claimreview","url":"https://www.aversusb.net/compare/flask-vs-starlette)","inLanguage":"en-US","isAccessibleForFree":true,"conditionsOfAccess":"Free","claimReviewed":"Flask vs Starlette","reviewBody":"Flask is a traditional, mature WSGI microframework with synchronous request handling and a massive ecosystem, while Starlette is a modern ASGI framework with built-in async/await support and superior performance for high-concurrency applications. Flask dominates legacy projects and learning, while Starlette excels in real-time, streaming, and high-load scenarios.","datePublished":"2026-07-07T13:39:28.053Z","dateModified":"2026-07-07T13:39:30.488Z","reviewRating":{"@type":"Rating","ratingValue":5,"worstRating":1,"bestRating":5,"alternateName":"High Confidence"},"author":{"@type":"Organization","@id":"https://www.aversusb.net/#organization","name":"A Versus B","url":"https://www.aversusb.net"},"itemReviewed":{"@type":"WebPage","@id":"https://www.aversusb.net/compare/flask-vs-starlette)","url":"https://www.aversusb.net/compare/flask-vs-starlette)","name":"Flask vs Starlette","inLanguage":"en-US"}}}