Skip to content
effecthub

Langflow vs Sim

Two fact sheets from our own research, side by side — pricing, platforms, API access and status re-checked by us rather than quoted from the vendors. Sim publishes a starting price ($25); Langflow does not. Both have a free tier. Both ship a public API.

LangflowOpen-source visual builder for LLM agents and RAG flows, deployable as an HTTP API or an MCP server.SimOpen-source workspace for building AI agents from a visual canvas, a prompt, or code

Side by side

FactLangflowSim
CategoryLLM Orchestration FrameworksAgent Frameworks & Orchestration
Pricing modelFreeFreemium
Starts at—$25 seat_month
Public APIYesYes
PlatformsWeb, macOS, Windows, Linux, APIWeb, API
CompanyLangflowSim, Inc
Last verifiedSep 6, 2026Sep 6, 2026

What our research says

Langflow

Langflow is the visual layer most teams reach for when a flow needs to be shown to someone who does not write Python, and the escape hatch into real code keeps it from becoming a toy. Deploying a flow as an API or MCP server in one step is the feature that earns it a place in production. The gap is commercial: no published pricing, no named vendor on the site, and support only via a contact form.

Pros

  • MIT-licensed with roughly 154,000 GitHub stars and an active release cadence
  • Any flow deploys as an HTTP API or an MCP server
  • Runs identically self-hosted, in the free cloud, or as a desktop app
  • Components can be edited as Python when the visual layer runs out

Cons

  • No pricing or support tiers published anywhere on the site
  • Desktop download requires a signup form and covers only Mac and Windows
  • The site names no operating company or jurisdiction
  • Visual flows get hard to reason about once they grow past a screen

Sim

Sim covers the unglamorous half of agent work — memory, tables, file storage, logs — in the same place you draw the workflow, and the open repository means you can host it yourself if the meter bothers you. The meter is the catch: credits are the unit of everything, and an agent that loops or fans out consumes them faster than the per-seat headline suggests.

Pros

  • Three ways to build the same agent: visual canvas, prompt, or code
  • Ships knowledge bases, data tables and file storage alongside the workflow engine
  • Open source on GitHub with a documented self-hosting route
  • Free tier of 1,000 monthly credits, one workspace and 5 GB of storage

Cons

  • Every plan is metered in credits, so cost tracks usage rather than headcount
  • Concurrency is capped per plan — 10 simultaneous executions on Free, 50 on Pro
  • SSO, access control and SOC2 paperwork sit behind the quoted Enterprise tier

Which one fits

Choose Langflow if you need

  • teams prototyping RAG and agent flows visually before coding them
  • self-hosters who want an MIT-licensed orchestration layer
  • exposing a flow to other tools as an MCP server

Choose Sim if you need

  • Teams that want a visual agent builder they can also self-host
  • Connecting agents to many SaaS tools without writing the glue code
  • Prototyping an agent and keeping the traces to debug it afterwards

More comparisons

All Sim alternatives →Browse all LLM Orchestration Frameworks →