15,347 tools
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Free planMaps
OpenStreetMap is a collaborative project that builds a free, editable map of the world from community contributions. Mappers add and maintain roads, trails, stations, and points of interest using open data licensing, powering thousands of apps, devices, and humanitarian mapping efforts worldwide.
Free planAssistant
OpenSumi is an open-source framework for building desktop or cloud IDE products quickly. It supports VS Code and OpenSumi extensions, customizable UI modules, and deployments in Electron or web containers, with customer examples from Alipay and Taobao mini-program studios.
Free planAssistant
OpenTag is a model-agnostic AI coworker for Slack and Microsoft Teams. It routes tasks across many LLMs, connects company tools and knowledge, runs secure cloud agents with approval gates, and supports scheduled automations triggered by chat or external events.
No free planAssistant
OpenTools provides an OpenAI-compatible API for LLM tool use across the MCP ecosystem. Developers call one completions endpoint, attach MCP tool references such as maps or search, swap models without rewriting clients, and pay unified at-cost token billing.
Free to startTransit
OpenTripPlanner is an open source family of projects for multimodal passenger information and transportation network analysis. Its Java server builds itineraries combining transit, walking, bicycling, and driving using OpenStreetMap and GTFS data, exposed through web APIs and client libraries used by regional journey planners worldwide.
Free planGaming
OpenTTD is an open source simulation game based on Transport Tycoon Deluxe that recreates and extends the classic transport-building gameplay. It adds larger maps, stable multiplayer for many players, dedicated servers, IPv6 support, NewGRF customization, and numerous quality-of-life tools under the GPL v2 license.
Free tier unknownResearch
OpenVAS is the Open Vulnerability Assessment Scanner maintained in the Greenbone ecosystem for finding security issues in networks and hosts. The openvas.org site introduces OPENVAS by Greenbone as a vulnerability scanner project with links to Greenbone community and commercial offerings.
Free planCode
OpenVDB is an open-source C++ library and file format for efficiently storing and manipulating sparse volumetric data such as smoke, fire, and other FX volumes. The project site welcomes visitors to documentation, downloads, and community resources for integrating OpenVDB into DCC tools and renderers.
Free tier unknownAssistant
OpenVector builds vision-language-action systems that connect live video streams to frontier VLMs for real-time understanding. Teams describe tasks in plain English, review generated workflows, and automate follow-up actions in business software when camera conditions are met.
Free planMessaging API
OpenWA is a free, open source, self-hosted WhatsApp HTTP API gateway for developers who want full control of messaging infrastructure. It provides REST endpoints, multi-session support, webhooks, a web dashboard, pluggable databases and storage, optional Redis queues, and swappable WhatsApp engines without vendor lock-in.
Free planCode
OpenWebhook provides a free webhook tester and inspector plus optional OpenWebhook Pro for permanent endpoints. The service captures HTTP requests in real time, exposes headers and payloads, supports forwarding to multiple HTTPS destinations, and offers CLI and MCP integrations for coding agents.
Free planInfrastructure
Apache OpenWhisk is an open-source serverless platform that runs functions in response to triggers from HTTP requests, feeds, or scheduled rules. The project packages actions in containers, exposes a REST API and wsk CLI, and supports multiple language runtimes so teams can self-host event-driven workloads at scale.
Free tier unknownCode
Openwork runs a crew economy where AI Claws execute missions and human Pilots oversee them on Base. Participants deploy agents, compete in hackathons, and earn $OPENWORK tokens while the marketplace API supports competitive bidding with on-chain escrow.
Free to startEvent Tracking
Operational is an open source event tracker built for tech products and SaaS operators who need a live feed of signups, payments, webhooks, cron jobs, and errors.
Free tier unknownResearch
Opinly automates SEO growth with site audits, keyword tracking, AI content generation, backlink exchange, competitor analytics, and LLM visibility monitoring.
Free planResearch
OPNsense is an open-source firewall and routing platform based on FreeBSD, offering VPN, traffic shaping, IDS/IPS, and extensive plugin extensions. The project site describes OPNsense as a feature-rich platform for network protection with community downloads and commercial support options.
Free planAssistant
Opslane is an open-source error tracker that records sessions, ranks user-impacting bugs, and opens verified fix pull requests via coding agents.
Free planCode
OptaPlanner is an Apache KIE constraint-satisfaction engine for planning and scheduling problems such as routing, staffing, and resource allocation. The optaplanner.org domain now redirects to the Apache KIE incubating site, which lists OptaPlanner alongside Drools, jBPM, and Kogito as open-source business automation components.
Free tier unknownImages
OptiClean is an AI photo and video cleanup app for macOS and iOS that removes unwanted people, objects, text, logos, and watermarks from media. The homepage highlights quick retouch workflows, standalone DMG download, and FAQ coverage of privacy and resolution handling.
Free tier unknownAssistant
Optifye deploys AI cameras on factory lines to monitor operator efficiency and standard operating procedures in real time. Operations leaders digitize manual processes, compare line performance, catch SOP deviations early, and reduce scrap with continuous shop-floor visibility.
Free to startEssay feedback
Optimize AI reviews essay drafts against a particular teacher’s grading style. It predicts a grade range, breaks feedback down by rubric and attaches sentence-level comments and suggested rewrites, with confidence informed by examples of the teacher’s graded work.
Free planVideo
OpusClip turns long videos into short viral clips with AI reframing, animated captions, B-roll, and social scheduling. The homepage targets creators and marketers who want one-click repurposing for TikTok, YouTube Shorts, Instagram Reels, and related channels.
Free planVideo
OpusClip Captions is part of OpusClip, an AI video repurposing platform that turns long videos into short clips with animated captions and social-ready exports. The captions route sits on OpusClip’s clipping product marketed for creators publishing viral shorts.
Free tier unknownAssistant
OpusWebsite at opus.ai is a client-rendered OpusAI web experience described as utilitarian luxury for the digital age. The public homepage loads as a single-page app backed by Opus API infrastructure, but marketing copy and pricing were not available in server-rendered HTML during review.
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