AI Tools

Search and filter curated AI tools. Find the right tool for your task.

How we rank tools

Each tool shows verification (how recently we checked the link), link health (whether the URL works), and trust (0–1, combining both). Verified + HTTPS = highest trust. Pending = not yet checked. Stale = last check was 1–3 days ago. Failed = over 3 days.

Hex

Checked 41m agoLink OKPro

A collaborative data workspace combining SQL notebooks, Python notebooks, and AI assistance in one browser-based platform for data analysis, reporting, and building interactive data apps. Hex's Magic AI assistant writes and explains SQL and Python code from natural language descriptions, generates charts from plain English requests, and helps debug query errors. The notebook environment supports SQL cells, Python cells, and interactive widgets side by side, making it easy to pull data with SQL, process it with Python, and visualize it with Plotly or Altair in the same document. A shared workspace allows teams to collaborate on data notebooks and publish polished, interactive data apps from notebooks with one click. Plans start at $24/month for teams. Popular with data analysts, data scientists, and analytics engineers who want a modern collaborative notebook experience with AI assistance.

LanceDB

Checked 41m agoLink OKFree plan available

An open-source, serverless vector database that runs embedded in-process without a separate server, making it as easy to add to a project as SQLite. LanceDB stores data in the Lance columnar format, which supports both random access and fast sequential scans, enabling hybrid full-text and vector search in the same database file. It handles multimodal data including text, images, audio, and video natively. Because LanceDB runs embedded without a separate process, it is well-suited for local AI applications, Jupyter notebooks, and edge deployments where running a separate vector server is impractical. LanceDB scales to disk-based storage for datasets larger than memory. A managed cloud version is available. Free and open-source under Apache 2.0. Popular with developers building local AI assistants, data science workflows, and lightweight AI apps that need vector search without infrastructure overhead.

LangSmith

Checked 41m agoLink OKFree plan available

A developer platform from LangChain for building, debugging, testing, and monitoring LLM applications in production. LangSmith provides full observability into every LLM call inside an application: input prompts, model responses, latency, token counts, and the full execution trace of multi-step agent workflows. A Dataset and Evaluation module lets developers build test datasets and run automated evaluations to measure output quality as models or prompts are updated. A Prompt Hub stores and versions prompts, enabling teams to track changes and A/B test variations systematically. The Playground allows prompt iteration with full trace visibility. LangSmith works with any LLM framework including LangChain, LlamaIndex, OpenAI SDK, and raw API calls. A free tier covers 5,000 traces per month; paid plans start at $39/month for higher volumes. Used by AI engineers and development teams building production LLM applications who need visibility into what is happening inside their AI pipeline.

LiteLLM

Checked 41m agoLink OKFree plan available

An open-source Python library and proxy server providing a unified API interface for calling over 100 different LLM providers through a single OpenAI-compatible format. Developers write code against the LiteLLM interface once and switch between OpenAI, Anthropic, Azure OpenAI, Google Gemini, Cohere, Mistral, Ollama, and many others by changing a single model string without rewriting API call logic. The LiteLLM Proxy Server mode adds a production-grade gateway with load balancing across multiple API keys, automatic retries and fallbacks, cost tracking per team or project, rate limiting, and logging to observability tools. Budget controls prevent individual teams from exceeding allocated API spend. Open source under MIT license on GitHub; a hosted proxy option is available. Popular with MLOps engineers, AI platform teams, and developers working with multiple LLM providers who need a single unified interface.

Milvus Open-Source Vector

Checked 41m agoLink OKFree plan available

Open-source vector database for scalable similarity search. Provides efficient storage and retrieval of vector data. Includes support for large-scale vector datasets. Used for image search and recommendation. Differentiator: scalable vector storage. Integrates with popular business tools and platforms. Supports multiple use cases and deployment scenarios. Includes comprehensive documentation and support resources. Designed for ease of use and quick implementation. Scales from startups to enterprise organizations.

MLflow Enterprise

Checked 41m agoLink OKEnterprise

Enterprise edition of MLflow for managing the complete machine learning lifecycle at scale. Tracks experiments with parameters, metrics, and artifacts. Manages model registry and model serving. Provides project packaging and reproducibility. Team collaboration and governance features. Integrates with existing ML infrastructure. Open source foundation with enterprise support. Used by large organizations with complex ML needs. Scales to many models and experiments.

Neptune.ai

Checked 41m agoLink OKFree plan available

An MLOps platform focused on experiment tracking, metadata storage, and model monitoring for data science teams. Neptune logs training runs with detailed metadata: hyperparameters, metrics, plots, code versions, hardware utilization, and custom artifacts, all stored in a searchable dashboard for comparison across experiments. The flexible data model allows logging any type of artifact including large files, images, confusion matrices, and audio samples. Integration with major training frameworks including PyTorch, TensorFlow, Keras, XGBoost, scikit-learn, and HuggingFace typically requires only two to three lines of code. Neptune is particularly valued by research teams for its flexibility in what can be tracked compared to more opinionated platforms. A team collaboration layer allows sharing experiments and annotating results. Free plan covers individual use; paid plans start at $49/month for team features and higher metadata storage.

Portkey AI

Checked 40m agoLink OKFree plan available

Open-source AI gateway for routing, caching, and monitoring LLM API calls.

Qdrant Vector Database

Checked 40m agoLink OKPro

Open-source and commercial vector database for similarity search. Provides vector storage, search, and retrieval with filtering. Includes REST and gRPC APIs. Used for semantic search and recommendation systems. Differentiator: production-ready vector search. Integrates with popular business tools and platforms. Supports multiple use cases and deployment scenarios. Includes comprehensive documentation and support resources. Designed for ease of use and quick implementation. Scales from startups to enterprise organizations.

Ray

Checked 40m agoLink OKFree plan available

An open-source distributed computing framework for scaling Python AI and ML workloads from a single machine to a large cluster without rewriting code. Ray's core model lets any Python function run as a distributed task and any Python class run as a distributed stateful actor, making parallel and distributed execution almost as easy as regular Python. Ray Tune provides distributed hyperparameter optimization across hundreds of parallel training jobs. Ray Train scales model training in PyTorch and TensorFlow across multiple GPUs and machines. Ray Serve deploys ML models as production online services with batching, autoscaling, and model composition support. Ray Data handles large-scale data preprocessing in parallel pipelines. Used by every major AI company and research lab for scaling LLM training, reinforcement learning environments, and inference workloads. Open source under Apache 2.0 on GitHub; managed cloud version is Anyscale. Used by companies including OpenAI, Anthropic, and Uber.

Semantic Kernel

Checked 40m agoLink OKFree plan available

Microsoft's open-source AI orchestration SDK for building AI agents and copilot experiences in C#, Python, and Java. Semantic Kernel provides abstractions for connecting LLMs from OpenAI and Azure OpenAI with native code functions, memory stores, and planners that let AI models invoke application logic. The Planner component lets an AI model decompose a goal into a sequence of function calls, enabling multi-step agentic workflows where the model can search a database, call an API, write a file, and summarize results in a single user request. Memory integration supports vector database-backed semantic memory retrieval. A Process Framework enables designing multi-agent systems with defined coordination patterns. Used heavily within Microsoft's own products and deeply integrated with Azure AI services. Open source on GitHub under MIT license. Popular with .NET development teams and enterprises building copilots on the Azure platform.

Supabase Postgres Platform

Checked 40m agoLink OKPro

Open-source Firebase alternative using PostgreSQL backend. Provides real-time subscriptions, authentication, and storage. Includes vector search and edge functions. Used for modern web applications. Differentiator: PostgreSQL with realtime. Integrates with popular business tools and platforms. Supports multiple use cases and deployment scenarios. Includes comprehensive documentation and support resources. Designed for ease of use and quick implementation. Scales from startups to enterprise organizations.

Vectara

Checked 40m agoLink OKFree plan available

An enterprise RAG platform providing a fully managed, API-first service for building semantic search and AI-powered question answering systems over private data. Vectara handles the complete RAG pipeline as a service: document ingestion and chunking, embedding generation, vector storage, hybrid search, reranking, and answer generation, without the user needing to manage any infrastructure. The Grounded Generation feature produces answers that cite specific sections of ingested documents, reducing hallucinations and making outputs verifiable. A Hallucination Evaluation Model is a free open-source score for measuring how factually grounded any AI response is. Enterprise features include access control, multi-tenant data isolation, and SOC 2 compliance. Free plan covers 50MB of data and 200 queries per month; paid plans scale by data volume and query count. Used by enterprises building internal knowledge bases, customer support assistants, and document search systems.

Weaviate Vector Database

Checked 40m agoLink OKPro

Open-source vector database for semantic search and similarity matching. Provides HNSW algorithm, hybrid search, and built-in ML models. Includes GraphQL API and integrations. Used for AI and semantic applications. Differentiator: built for vector search. Integrates with popular business tools and platforms. Supports multiple use cases and deployment scenarios. Includes comprehensive documentation and support resources. Designed for ease of use and quick implementation. Scales from startups to enterprise organizations.

AskYourPDF

Checked 42m agoLink OKFree plan available

A document AI platform enabling natural language conversation with uploaded PDFs, Word documents, text files, and PowerPoint files, as well as documents loaded from URLs or Google Drive links. AskYourPDF stores documents in a personal knowledge library and lets users query across multiple documents simultaneously, asking a question and getting a synthesized answer from several sources. A team workspace lets shared documents be queried by all members. An API allows developers to embed document Q&A into their own applications. The platform also supports web-based research where users submit a URL and ask questions about the page content. Free plan covers basic document chat with limited messages; Pro is $9.99/month. Popular with legal professionals, consultants, researchers, and business analysts who work with large volumes of document-based information.

Brilliant

Checked 41m agoLink OKPro

An interactive learning platform for building skills in math, science, data analysis, and computer science through guided problem solving rather than video lectures. Brilliant's approach is hands-on: each concept is learned by solving progressively harder problems with built-in hints, visual interactive simulations, and AI explanations of why an answer is wrong in context. Subjects covered include algebra, geometry, calculus, probability, statistics, logic, quantum computing, neural networks, Python programming, and data science. The AI adapts the difficulty of problems dynamically based on performance and identifies knowledge gaps to address. Unlike Coursera or Khan Academy, Brilliant does not offer certifications but focuses purely on deep conceptual understanding. Free trial includes some content; Brilliant Premium is $24.99/month or $149.99/year for full access. Used by students, working professionals developing technical skills, and lifelong learners.

ChatPDF

Checked 41m agoLink OKFree plan available

A web tool that lets users upload any PDF document and have a natural language conversation with its contents using AI. Users ask questions about the document and ChatPDF retrieves and synthesizes relevant passages to generate a direct answer with page references. It works for research papers, legal contracts, financial reports, textbooks, manuals, and any other document-based content. The tool handles documents up to several hundred pages and retains context across multiple questions in the same session, making it possible to explore a complex document through conversation rather than linear reading. A summary is auto-generated when a document is first uploaded. Free plan covers 2 PDFs per day up to 120 pages each; Pro is $5/month for more PDFs, larger files, and higher message limits. Popular with students reading academic papers, lawyers reviewing contracts, and analysts processing reports.

Connected Papers

Checked 41m agoLink OKFree plan available

A visual research tool that generates a graph showing relationships between academic papers based on citation networks and semantic similarity. Researchers enter a seed paper they consider relevant to their topic, and Connected Papers builds a visual map of related work, clustering similar papers together and showing how closely each paper is connected to the seed through edge thickness and node proximity. This helps researchers quickly identify the most influential papers in a field, find seminal works they might have missed, and see which papers are highly cited together. Papers can be clicked to open in their source database. The graph view is more intuitive for exploring a field than a list of search results, making it especially useful at the start of a literature review. Free plan allows 5 graph builds per month; Pro is $3/month for unlimited graphs. Popular with academics, graduate students, and research analysts.

Duolingo AI

Checked 41m agoLink OKFree plan available

Duolingo has integrated AI throughout its language learning app, with the most significant additions in Duolingo Max, the premium AI tier. Explain My Answer is an AI tutor that explains why a user's response was correct or incorrect in natural language rather than showing a generic error message. Roleplay lets users practice real-world conversational scenarios with an AI character in the target language, covering situations like ordering food, asking for directions, or making plans. The existing spaced repetition algorithm uses AI to schedule vocabulary review at the optimal time for each individual learner. Duolingo's AI also powers audio comprehension practice, adaptive hint systems, and sentence-level translation exercises. Free tier covers core lessons; Duolingo Max with full AI features is $29.99/month. Duolingo has over 500 million registered users globally, making it the world's most used language learning platform.

Elsa Speak

Checked 41m agoLink OKFree plan available

An AI English pronunciation and speaking coach app that uses speech recognition to detect and correct pronunciation errors at the level of individual phonemes. Unlike apps that only transcribe speech, Elsa analyzes precisely which sounds are mispronounced, why they are incorrect, and provides targeted exercises to correct the specific mouth position and airflow needed for each sound. The app builds a personal pronunciation profile for each learner based on their native language and detected weaknesses, then creates a customized learning path. Elsa covers over 22,000 English words and includes practice with sentences, conversations, and business scenarios. Users practice being understood in meetings, on video calls, at the doctor, and in other real-life situations. Free plan includes limited daily lessons; Elsa Pro is $11.99/month or $59.99/year. Used by over 7 million people in 101 countries learning to speak English more clearly.