FastGPT vs Sim.ai

Side-by-side comparison of two AI agent tools

F
FastGPTopen-source

FastGPT is a knowledge-based platform built on the LLMs, offers a comprehensive suite of out-of-the-box capabilities such as data processing, RAG retrieval, and

S
Sim.aiopen-source

Sim is the collaborative workspace to build, deploy, and monitor AI agents and workflows. Used by 100,000+ builders.

Metrics

FastGPTSim.ai
Stars29.8k29.8k
Star velocity /mo2.5k2.5k
Commits (90d)4462.4k
Releases (6m)1010
Overall score0.84414728425193990.8900603737544774

FAQ

Which is more popular, FastGPT or Sim.ai?
FastGPT has more GitHub stars (29,774 vs 29,756).
Which is more actively developed, FastGPT or Sim.ai?
Sim.ai had more commits in the last 90 days (2,417 vs 446).
Should I use FastGPT or Sim.ai?
Compare their capabilities, limitations and "best for" notes above. Both are open source, so trying each on a small task is the fastest way to decide.
FastGPT vs Sim.ai (2026): GitHub Stats, Features & Which to Choose