Express is a mature, widely-adopted Node.js framework with the largest ecosystem and community support, while Fastify is a newer, high-performance alternative that handles 2-3x more requests per second and includes built-in validation and serialization. Express dominates in production deployments, but Fastify excels in performance-critical applications.
Express vs Fastify — Side-by-side comparison on A Versus B
Mature, minimalist Node.js web framework with largest middleware ecosystem and production adoption.
High-performance Node.js framework optimized for speed with built-in schema validation
Throughput Performance. Time to First Release. npm Weekly Downloads. Startup Time. Built-in Schema Validation. GitHub Stars. Production Usage (Fortune 500)
Choose Express if you need maximum community support, the largest middleware ecosystem, and working with established production systems—it remains the industry standard for web APIs. Choose Fastify if you're building new high-performance services, microservices, or serverless functions where throughput and startup time are critical, and you prefer built-in features like schema validation over external middleware.
Express.js: No (requires middleware) | Fastify: Yes (JSON Schema native)
Express.js: 10,000+ third-party packages | Fastify: 2,000+ specialized plugins
Express.js: ~120 ms | Fastify: ~400-600 ms
Express.js: None (third-party required) | Fastify: N/A
Express.js: Third-party package required | Fastify: N/A
Development Speed (Median Project Timeline)
Express.js: Manual (requires express-swagger-jsdoc or similar) | Fastify: N/A
Express.js: Optional (TypeScript) | Fastify: N/A
Express.js: ~55 MB per instance | Fastify: ~28
Express.js: Native Socket.io integration | Fastify: N/A
Express.js: Requires Node bindings/bridges | Fastify: N/A
Express.js: 64,000+ stars | Fastify: N/A
Express.js: 16.2 million | Fastify: 1.2 million
Express.js: Via @types/express | Fastify: N/A
Express.js: ~8,000 req/s | Fastify: ~37,500
Express.js: Partial (middleware adapters needed) | Fastify: N/A
Express.js: Callback-based (req, res, next) | Fastify: N/A
Express.js: ~20,000,000 (npm) | Fastify: N/A
Express.js: 15 years (since 2010) | Fastify: N/A
Express.js: No (manual setup with Swagger) | Fastify: N/A
Express.js: ~2,300,000 (NPM) | Fastify: N/A
Express.js: Promise/async-await (event loop) | Fastify: N/A
Express.js: Not included, external libraries needed | Fastify: N/A
Express.js: Yes (Promises/callbacks) | Fastify: N/A
Express.js: 28.4 million | Fastify: ~1.1M weekly downloads
Express.js: ~10,000 req/s | Fastify: N/A
Express.js: No (requires Swagger, apiDoc packages) | Fastify: N/A
Express.js: No (requires middleware like celebrate) | Fastify: N/A
Express.js: Limited: TensorFlow.js only, requires external API calls | Fastify: N/A
Express.js: ~64,000 stars | Fastify: N/A
Express.js: Yes - runs directly with Node.js | Fastify: N/A
Express.js: Limited via adapters | Fastify: N/A
Express.js: Optional (requires setup) | Fastify: N/A
Express.js: None (requires external libraries) | Fastify: N/A
Express.js: 8,000-12,000 req/sec | Fastify: N/A
Express.js: 5-7 days for JS developers | Fastify: N/A
Express.js: 32% of Node.js projects | Fastify: N/A
Express.js: ~8,000 req/sec | Fastify: N/A
Express.js: ~40-100 MB (with node_modules) | Fastify: N/A
Express.js: ~10,000 per instance | Fastify: N/A
Express.js: ~20M+ (NPM/week) | Fastify: N/A
Express.js: 2.3M packages | Fastify: N/A
Express.js: Manual setup required | Fastify: N/A
Express.js: 18M+ weekly downloads | Fastify: N/A
Express.js: Requires wrapper middleware (co, async-await-handler) | Fastify: N/A
Express.js: 12+ years (released 2010) | Fastify: N/A
Express.js: N/A | Fastify: ~40,000 req/s
Express.js: N/A | Fastify: Plugin required (@fastify/ajv-compiler)
Express.js: N/A | Fastify: Manual tsconfig + compilation setup
Express.js: N/A | Fastify: 12% of surveyed enterprise Node teams
Express.js: N/A | Fastify: ~45,000 req/sec
Express.js: N/A | Fastify: 15+ official plugins
Express.js: N/A | Fastify: Optional, works with JavaScript
Express.js: N/A | Fastify: No (manual or third-party)
Express.js: N/A | Fastify: Official built-in types
How to choose between Express.js and Fastify
Express vs Fastify — Structured Comparison Data
Machine-readable comparison dataset for Express vs Fastify. Contains 120 attribute comparisons, 5 FAQ pairs.
Express vs Fastify — Attribute Category Vocabulary
Taxonomy of attribute categories used to classify comparison data for Express vs Fastify.
Is Express dead? Should I still use it in 2026?
No, Express is not dead. It remains the most widely-used Node.js framework with 15.8M weekly downloads and 85% adoption in surveyed Fortune 500 companies. However, new high-performance applications often choose Fastify or other alternatives. Express is ideal for maintaining existing projects and traditional REST APIs where community support matters more than raw throughput.
Why is Fastify so much faster than Express?
Fastify achieves 2-3x higher throughput through several optimizations: (1) asynchronous request routing using trie-based matching, (2) automatic JSON serialization instead of relying on middleware, (3) built-in schema validation that pre-compiles validators, and (4) lower overhead per request. Express's middleware-based architecture, while flexible, adds latency to each request cycle.
Can I migrate an Express app to Fastify?
Migration is possible but requires significant refactoring. Express middleware and Fastify plugins work differently—Express uses a chain-of-responsibility pattern while Fastify uses a plugin system. Simple APIs may take 1-2 weeks to migrate; complex ones with extensive custom middleware may take 2-4 weeks. Most teams create new services in Fastify rather than converting legacy Express apps.
Fastify is generally better for microservices due to lower startup time (15ms vs 40ms), higher throughput, and built-in schema validation that prevents cross-service data mismatches. However, Express remains viable if microservices are long-running and community familiarity is a priority. For serverless microservices, Fastify's startup time is a critical advantage.
Do I need to learn Express before Fastify?
No. While Express knowledge helps with general Node.js concepts, Fastify has its own paradigms (hooks, schema validation, plugin system) that require separate learning. Developers can learn Fastify directly; starting with Express is not a prerequisite. However, Express familiarity makes the industry job market broader since 85% of surveyed companies still use it.
How to Choose Between Express.js and Fastify
Throughput Performance: Express.js has ~15,000 req/s, while Fastify has ~30,000-40,000 req/s.
Time to First Release: Express.js has 2010, while Fastify has 2016.
npm Weekly Downloads: Express.js has ~15.8 million, while Fastify has ~1.2 million.
Startup Time: Express.js has ~40ms, while Fastify has ~15ms.
Built-in Schema Validation: Express.js has No (requires middleware), while Fastify has Yes (JSON Schema native).
GitHub Stars: Express.js has ~64,000, while Fastify has ~32,000.
Consider: Production Usage (Fortune 500)
Production Usage (Fortune 500): Express.js has ~85% of surveyed companies, while Fastify has ~12% of surveyed companies.