Why Vespa

AI Needs Search

Vespa unifies retrieval and machine-learned ranking in a single scalable platform, built to power the most demanding AI applications at speed and scale.

Search Infrastructure for the GenAI Era

Modern enterprises face a fundamental barrier to AI adoption: the inability to retrieve and operationalize data in real time. Information is fragmented across systems and stored in inconsistent formats—PDFs, logs, free text, and semi-structured data—making it difficult to unify, index, and serve to AI models. This lack of AI-ready infrastructure creates friction when deploying retrieval-augmented generation (RAG), recommendation systems, or intelligent search at scale. As a result, many promising AI initiatives stall not because of model performance, but because the underlying data systems can’t keep up.

 

Enter the AI Search Platform

An AI Search Platform operationalizes AI by making retrieval smarter, faster, and more scalable. It combines classical search with modern AI techniques like vector search, machine-learned ranking, and real-time inference. These platforms serve as the foundation for applications that demand context-aware, highly relevant results at speed and scale.

Unlike legacy search stacks that focus on sparse term-based retrieval, AI Search Platforms are designed to support advanced use cases like RAG, semantic search, and personalization. They natively handle complex data structures such as tensors, integrate with machine learning workflows, and scale to meet enterprise demands for performance, accuracy, and flexibility.

Vespa: The Leading AI Search Platform

Vespa is an AI Search Platform purpose-built to power RAG applications that need quality and scalability. It allows you to search data consisting of vectors, tensors, full text, and structured fields together, and rank and make inferences in the data using tensor math and machine learning—at any scale.

Proven in production for over a decade, Vespa is trusted by organizations like Perplexity, Spotify, Yahoo, Otto, and OkCupid—companies that depend on fast, accurate retrieval at scale. Designed to meet the needs of modern AI teams, Vespa delivers on the four pillars that matter most: performance, accuracy, scalability, and flexibility.

 

Vespa Use Cases

Search

Vespa combines advanced text search with full support for tensor-based retrieval. It offers linguistic processing, snippet generation, and machine-learned ranking using features from BM25 to positional relevance.

Generative AI (RAG)

Vespa supports hybrid RAG with text, vector, and token-based retrieval, plus ML ranking—scaling to any data size or query volume without compromising relevance or performance.

Recommendation & Personalization

Vespa combines fast filtering, on-node model evaluation, and high-throughput updates—supporting real-time relevance tuning, behavior-driven ranking, and dynamic content adaptation at scale, with up to 100k writes per second per node.

Vespa by Design: Core Architectural Pillars

Performance: Low Latency, Lower Cost

  • The challenge: AI systems often suffer from slow queries, system bottlenecks, and expensive ranking stages.
  • Vespa’s advantage: Vespa co-locates data and computation, minimizing network overhead. Its multi-phase ranking pipeline evaluates results in stages, ensuring fast, resource-efficient performance across massive datasets.

Accuracy: Relevant, Contextual Results

  • The challenge: Failing to retrieve the most relevant information for a particular situation leads to low quality AI responses and user experiences.
  • Vespa’s advantage: Vespa supports hybrid retrieval—keyword, structured, vector, and tensor, and applies distributed machine-learned ranking combining hundreds of signals needed to deliver state-of-the art relevance in typical real-world applications.

Elastic Scalability: Built for Growth

  • The challenge: Many systems cannot deliver both high quality and scalability, as that requires co-locating all data modalities and computation on the same distributed set of nodes.
  • Vespa’s advantage: Vespa is proven to deliver low latency and reliability at scales up to hundreds of billions of documents and hundreds of thousands of queries per second. You can change the machine resources powering clusters both up and down, simply by changing a configuration value, while serving queries and writes in real time.

Flexibility: Fit for Complex Requirements

  • The challenge: Off-the-shelf tools can’t adapt to domain-specific data or evolving AI needs and are locked into specific use cases..
  • Vespa’s advantage: Vespa enables deep customization, supporting custom document schemas, external ML models (ONNX, GBDT), and fully configurable query pipelines. It handles both structured and unstructured data, so teams can adapt Vespa to their use case—not the other way around.

Proven in the Real World

Vespa was initially developed at Yahoo to solve the challenge of applying machine-learned ranking and real-time personalization at internet scale. Today, it supports over 150 mission-critical applications, handles more than 800,000 queries per second, and serves nearly one billion users globally, powering one of the largest-scale deployments of real-time AI in the world.

Delivering RAG for Perplexity

Vespa is the engine behind Perplexity’s retrieval-augmented generation (RAG) system, delivering low-latency, contextually relevant answers across billions of documents. It enables dense and sparse retrieval, approximate nearest neighbor (ANN) search, and large-scale ranking using expressive tensor models—executed directly on stored data for maximum efficiency.

Read more about Vespa at Perplexity.

Explore what makes Vespa the #1 AI Search Platform

Customer Stories

Learn how innovators like Perplexity, Spotify, and Yahoo are using Vespa to serve billions of queries and scale their AI systems efficiently.

Vespa vs Alternatives

Compare Vespa to Elasticsearch, Solr, and others. See how Vespa’s unified approach outperforms split-stack architectures in complex AI workflows.

Analyst Perspective

Read what independent analysts are saying about Vespa’s unique position in the AI infrastructure ecosystem.

Performance Benchmark

See how Vespa performs in real-world workloads, including latency, throughput, and cost efficiency at scale, benchmarked against Elasticsearch.

Partner Support

Discover trusted partners with Vespa expertise who can help deliver your AI search applications and support your journey from design to deployment.

Vespa Blog

Explore practical guides and thought leadership on AI search. Our blog covers best practices and emerging trends for engineers working with Vespa.

Vespa: Purpose-Built AI Search Platform

Vespa is a platform engineered for real-time search and inference at scale. Unlike general-purpose engines, Vespa natively supports the needs of AI-powered applications—from semantic retrieval to complex ranking and dynamic decisioning.

Offered as open source and a fully managed cloud service, Vespa gives teams full control over their stack—supporting custom data models, real-time updates, and horizontal scaling without compromising on latency or cost.