Letta

● Identity checked

Code · Vendor site 2026-10-04

Letta is an AI research lab and product company building stateful agents whose memory and capabilities evolve over time, originating from MemGPT research. It ships Letta Agent software, a CLI, and cloud plans for individuals, teams, and API developers.

Updated 2026-10-04View sources

Official website

Category: Code
Free access: Free plan supports up to three stateful agents with BYOK models including supported external coding plans
API access: Developer API plan offers usage-based billing with API keys and pay-as-you-go LLM costs

Is Letta right for you?

A good fit for

Engineers and teams building long-horizon coding or workflow agents that need durable memory and sandboxed execution.

Before you choose

Free tier caps stateful agents at three; Pro adds remote sandboxes, Letta Auto quota, and paid credits for hosted models.

Overview

Letta combines research on memory-native agents with a product stack for building agents that learn from experience, offered through free, Pro, team, and API pricing tiers.

What it can do

Features & capabilities

Unknown is different from unavailable. Each fact carries its own evidence.

Capability	Value	Evidence	Checked
Research lineage	Founded from MemGPT and virtual context management research out of UC Berkeley.	Facts sourced	2026-10-04
Letta Agent	Product site ships Letta Agent as self-improving software with evolving memory and skills.	Facts sourced	2026-10-04
CLI install	Homepage documents installing Letta via npm global package @letta-ai/letta-code.	Facts sourced	2026-10-04

Understand the total cost

Letta pricing & plans

Free

Free personal plan with agent cap

Agents: Up to three stateful agents
Models: Bring your own API keys and external coding plans

Pro

$20.00 /mo

Billed monthly on Letta docs pricing

Agents: Up to 20 stateful agents
Letta Auto: Weekly and monthly quota plus pay-as-you-go overage

API Plan

$20.00 /mo

Usage-based developer plan

Agents: Unlimited agents with usage-based fees
Usage: $0.10 per active agent per month plus tool execution charges

Explore pricing & history

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The practical questions

Frequently asked questions

What is Letta used for?

Does Letta have a free plan?

Free plan supports up to three stateful agents with BYOK models including supported external coding plans. This record lists ongoing free access; check the plan limits before starting.

How much does Letta cost?

The listed monthly price is $20.00 USD at monthly billing. See the plan cards for entitlements, billing commitments and seat minimums.

Can I use Letta through an API?

Developer API plan offers usage-based billing with API keys and pay-as-you-go LLM costs. API access and subscription access may have different terms; consult the linked sources.

What should I check before choosing it?

Free tier caps stateful agents at three; Pro adds remote sandboxes, Letta Auto quota, and paid credits for hosted models.

Price history

No retained pricing changes yet. A current price alone does not establish a historical trend.

How this profile is supported

Identity and profile

Reviewed vendor source

Read original source ↗

2026-10-04

Facts apply to the named version and check date. Send a sourced correction if something changed.