4+ Best Alternatives to Stack AI in 2026
No-code platform for enterprise AI agents and forms
Looking for an alternative to Stack AI? Below are 4 AI startups working in the same space — ranked by our Neuron score so the most credible options come first. Each card shows what makes the tool a viable substitute, pricing signals, and funding stage.
- 1View alternative →
Letta
UndisclosedMemory-first agents that learn and improve from experience with natural language.
Why it's similar: Shares categories with Stack AI — Form & Workflow.
💵 Free
- 2View alternative →
Relevance AI
UndisclosedAI Agents for Sales & GTM Teams to scale results without scaling headcount.
Why it's similar: Shares categories with Stack AI — Form & Workflow.
💵 Enterprise · Contact sales
- 3View alternative →
Botpress
UndisclosedThe complete AI agent platform for building, deploying, and monitoring AI agents powered by the latest LLMs.
Why it's similar: Shares categories with Stack AI — Form & Workflow.
💵 Free
- 4View alternative →
Voiceflow
UndisclosedBuild, launch, and scale advanced AI agents for support, lead generation, and beyond without code.
Why it's similar: Shares categories with Stack AI — Form & Workflow.
💵 Free
Frequently asked questions
What are the best alternatives to Stack AI?
The top-ranked alternatives to Stack AI on NeuronFeed are Letta, Relevance AI, Botpress, Voiceflow. Rankings are based on our Neuron score, which weighs funding, momentum and editorial signal.
Is there a free alternative to Stack AI?
Yes — Letta, Relevance AI, Botpress offer a free plans. See the pricing column for each alternative above.
How is this list ranked?
We rank alternatives by shared categories with Stack AI, then by our proprietary Neuron score (0–100) which combines funding, team quality, momentum, and editorial input. The list refreshes every 30 days.
Stack AI vs Letta — which is better?
It depends on use case. Letta (Memory-first agents that learn and improve from experience with natural language.) is the #1-ranked alternative. See the full side-by-side at /compare/stack-ai-vs-letta.
Explore more around Stack AI
Contextual paths to related AI startups, deals and rankings.