Agent Memory & RAG-as-a-Servicefreemium

Letta

Free BYOK plan supporting up to 3 stateful agents

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What Letta does

  • Free BYOK plan supporting up to 3 stateful agents
  • Stateful-agent runtime with persistent memory, desktop app, CLI and API
  • Open-source framework (formerly MemGPT) plus a managed cloud

Letta — straight answers

What is Letta?

Letta is listed under Agent Memory & RAG-as-a-Service, in the AI Agents & Automation category on Flocci AI Tools. Free BYOK plan supporting up to 3 stateful agents. It is freemium — a usable free tier with paid plans above it, and it lives at letta.com.

Is Letta free?

Letta is freemium: there is a free tier you can work in and paid plans above it. It is one of 426 freemium tools in the catalog, all labelled the same way so you are never surprised by a paywall.

Can I use Letta in a browser, or is there an app?

Letta works in a normal browser tab with no install. It is available on the web and the command line.

What can Letta do?

Letta does 3 things the catalog singles out: Free byok plan supporting up to 3 stateful agents; stateful-agent runtime with persistent memory, desktop app, cli and api; open-source framework (formerly memgpt) plus a managed cloud.

What is the best free alternative to Letta?

MemOS is the closest free alternative: it sits in the same Agent Memory & RAG-as-a-Service sub-category and is free. RAGFlow, Basic Memory and Cognee also start free. The full list is on the alternatives page.

See the full list →

Letta alternatives

Compare all alternatives →

Mem0

Agent Memory & RAG-as-a-Service
freemium
  • Free Hobby tier: unlimited end users, 10K add / 1K retrieval requests/month
  • Graph memory and entity linking for agent context
  • Open-source core plus managed cloud API
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Zep

Agent Memory & RAG-as-a-Service
freemium
  • Free plan: 10,000 monthly credits, 2 projects, 200ms retrieval
  • Graph RAG with automated context assembly from chat + business data
  • Temporal knowledge graph for tracking how facts change over time
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Supermemory

Agent Memory & RAG-as-a-Service
freemium
  • Free monthly usage allowance plus a Supermemory MCP server
  • Native connectors for Google Drive, Notion, OneDrive as memory sources
  • Deduplication so repeated content isn't rebilled
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RAGFlow

Agent Memory & RAG-as-a-Service
freeNew
  • Open-source RAG engine with deep document parsing and agent workflows
  • Grounded citations and template-based chunking
  • Self-host with Docker; bring your own LLM
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LightRAG

Agent Memory & RAG-as-a-Service
freeNew
  • Simple, fast graph-based RAG from HKU Data Science lab (EMNLP 2025)
  • Combines knowledge-graph and vector retrieval
  • Works with local or hosted LLMs
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Cognee

Agent Memory & RAG-as-a-Service
freeNew
  • Open-source memory platform that turns data into a knowledge graph plus vectors for agents
  • Python API with pluggable graph, vector and relational stores
  • Self-host free; cloud option exists
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Head-to-head comparisons

Letta vs Mem0Letta vs ZepLetta vs SupermemoryLetta vs RAGFlowLetta vs LightRAGLetta vs Cognee