Sim vs Retool

Use Retool when the internal tool needs a full app interface, and Sim when the tool is an AI agent or automation. Retool builds internal business applications with a React frontend and TypeScript backend, and its AppGen generates the UI, data queries, and bindings from a plain-English prompt while inheriting the org's existing authentication and access controls. Retool Agents is a separate product that combines deterministic code, LLM decisions, and human-in-the-loop steps. Sim combines agent, function, and human approval blocks in a single workflow builder, builds and edits workflows from natural language through Chat and Copilot, and deploys them as a REST API, a public chat interface, or an MCP tool.

Sim is built for AI agents first, while Retool's agent capabilities sit beside an internal app builder. Retool Agents usage is billed by the hour, separately from the monthly AI-credit allocation, and Retool documents no dedicated evaluation or guardrail framework for agent output, nor a way to publish an individual app or workflow as its own MCP tool. Sim includes an Evaluator block that scores outputs against named metrics, a Guardrails block for JSON validation, regex, hallucination scoring, and PII masking, reusable Agent Skills, and publishing of any deployed workflow as an MCP tool.

Retool is proprietary and closed-source, while Sim's core is licensed under Apache 2.0. Retool's pricing page lists self-hosting on its Enterprise plan, where a deployment still requires a Retool-issued license key, and its Docker Compose setup is for non-production testing only, so production self-hosting runs on Kubernetes with Helm. Sim can be self-hosted with Docker Compose or Kubernetes (Helm), and its enterprise features, such as SSO and audit logs, require a Sim Enterprise license.

Sim's knowledge base combines vector and full-text search and keeps sources in sync, while Retool Vectors is a managed vector store for uploaded content. Retool Vectors indexes text, PDFs, and web pages, and it generates embeddings with an OpenAI embedding model (text-embedding-ada-002 by default) that cannot be changed after a vector is created. Sim stores embeddings in pgvector alongside a full-text index, supports 15 file types with configurable chunking, uses connectors to continuously sync sources such as Google Drive, Confluence, and Slack, and shows chunk-level detail with a dedicated chunk editor.

Sim is an open-source AI workspace where teams build, deploy, and manage AI agents visually, conversationally, or with code. Retool is a low-code platform for building, deploying, and managing internal software (apps, workflows, and AI agents) that connect to databases, APIs, and LLMs. Teams considering a switch typically weigh licensing (Sim's core is Apache 2.0 and self-hostable), pricing model, and how AI-native the platform's agent-building experience is.

Sim is built specifically as an AI agent workspace, with native multi-LLM support, an in-editor AI Copilot, and a knowledge base with hybrid vector + keyword search. Retool's standout capability is full internal business applications, not just agent workflows: Retool builds full internal business applications, not just agent workflows: apps are now written in React on the frontend and TypeScript on the backend, giving teams a real app runtime instead of a proprietary component tree. AppGen lets users describe an app in plain English; Retool's agent generates the UI, data queries, and bindings from that prompt, wired to production data, with every generated app automatically inheriting the org's existing centralized authentication, role-based access controls, and data-access policies rather than having auth logic baked into the app code. One documented limitation of Retool is proprietary, closed-source core: Retool is proprietary and closed-source. The self-hosted deployment can be forked and customized and bundles open-source dependencies, but still requires a Retool-issued license key to run. No OSS license covers the product itself.

Sim can be self-hosted via Docker or Kubernetes with an Apache 2.0-licensed core, in addition to a managed cloud-hosted plan. Enterprise features such as SSO and audit logs require an Enterprise license. Retool's self-hosting position: Yes, on Enterprise: the pricing page lists Retool Cloud, self-hosted, or air-gapped deployment only on the Enterprise plan, while Free, Team, and Business include Retool Cloud.

Sim uses credit-based usage billing (Stripe); bring-your-own-key calls skip Sim's model and tool usage charge, while the base per-run charge still applies. Retool uses seat-based (separate builder vs.

Security is a like-for-like comparison, not a one-line verdict. Sim: SOC2. Retool: SOC 2 Type II, ISO/IEC 27001:2022, GDPR, and CCPA certifications, plus HIPAA via BAA on Enterprise. Check the Security & compliance rows above for the full breakdown, including SSO, audit logging, and data residency.

Sim: 28 provider integrations (OpenAI, Anthropic, Google/Gemini, Azure OpenAI, Azure Anthropic, Vertex, Bedrock, xAI, Mistral, DeepSeek, Groq, Cerebras, Fireworks, Together, Ollama, OpenRouter, and more), with OpenRouter, LiteLLM, vLLM, and Ollama resolving models dynamically at runtime rather than from a fixed list, so effective model reach extends well beyond the 28 named providers. Retool: direct providers OpenAI, Anthropic, and Google; cloud service providers AWS (Bedrock) and Azure (OpenAI); plus a "bring your own model" option. Sim also ships native human-in-the-loop approvals, a hybrid vector-plus-keyword knowledge base, and an in-editor AI Copilot that can read execution logs and directly edit the workflow to fix a failed run.

Documented limitations of Retool include proprietary, closed-source core: Retool is proprietary and closed-source. The self-hosted deployment can be forked and customized and bundles open-source dependencies, but still requires a Retool-issued license key to run. No OSS license covers the product itself.; docker self-hosted deployment explicitly not production-ready: The Docker Compose self-hosted setup (bundled Postgres container, no SSL configured) is for local and non-production testing only. Production self-hosting requires a Kubernetes/Helm deployment.; no dedicated built-in eval/guardrail framework documented: Retool documents governance controls (audit logs, RBAC, enterprise access controls) but no dedicated evaluation, testing, or guardrail framework for validating AI agent behavior or outputs before production use.; agents billed separately by the hour, outside the AI-credit pool: Retool Agents usage is metered and billed hourly, separate from the monthly AI-credit allocation used for app-building and AI actions. This adds a second, less predictable usage-based cost on top of seat pricing.

There is no automated one-click migration tool between Retool and Sim. Workflows and automations need to be rebuilt in Sim's visual builder, natural-language Chat surface, or API. Most teams start by recreating their highest-value automation first to validate the switch before migrating the rest.