E2B

Open-source cloud sandboxes for AI agents

E2B provides open-source sandboxed cloud environments that start in under 200ms for AI agents to execute code safely, powering hundreds of millions of sessions. Its sandboxes are widely used as the execution layer for agent evals and RL environments; customers include Perplexity and Hugging Face.

Used by 88% of the Fortune 100

Websitee2b.dev
DomainsAgents Infrastructure, Coding
LocationSan Francisco
Team size26-50
Founded2023
FundingSeries A, $21M (Insight Partners, July 2025); $32M total
FoundersVasek Mlejnsky @mlejva, Tomas Valenta

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