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Startups14,448Programs29

14,448 startups · 29 programs

Chatter

Acquired · Dead simple LLM testing and iteration

WebsiteYC profile

Why it ranks

How the rank works
11signal of 100 · rising 4
  • acquiredOutcome · YC, program pages, Acquisitions+4
  • went through YCProgram · this site+4
  • team of 2Team size · YC's directory+2.5

A sum of public facts, not a judgement and not investment advice.

Competitors

AIBPOptimaShared: model familyAntler 2025SingaporeStartup →AIDecipher AIShared: write testYC W24San FranciscoStartup →AIBaserunShared: aiops, llm, testingYC S23San FranciscoStartup →Developer toolsInactiveDimeShared: write test, feature, developerYC S21San FranciscoStartup →Developer toolsKarate LabsShared: write test, collaboration, developerYC W22WilmingtonStartup →
Companies closest to Chatter
Company
BPOptimaShared: model familyAntler 2025Not statedAI
Decipher AIShared: write testYC W24ActiveAI, Devtools
BaserunShared: aiops, llm, testingYC S23ActiveAI, Devtools
DimeShared: write test, feature, developerYC S21InactiveDevtools
Karate LabsShared: write test, collaboration, developerYC W22ActiveDevtools

Adjacent

AIOpenToolsShared: llmYC S23San FranciscoStartup →AIAcquiredHeliconeShared: aiops, llm, modelYC W23San FranciscoStartup →AIPareaShared: llm, test, evaluateYC S23New York CityStartup →AIConsensusShared: llmAI Grant Batch 3Startup →Developer toolsTermiusShared: collaboration featureYC W19AucklandStartup →
Companies next to Chatter
Company
OpenToolsShared: llmYC S23ActiveAI, Devtools
HeliconeShared: aiops, llm, modelYC W23AcquiredAI, Data, Devtools
PareaShared: llm, test, evaluateYC S23ActiveAI, Devtools
ConsensusShared: llmAI Grant Batch 3Not statedAI
TermiusShared: collaboration featureYC W19ActiveDevtools

Also from S23 in AI

All of S23
AIInactiveAtlaThe improvement engine for AI agentsYC S23LondonStartup →AIAutomorphicInfuse knowledge into language models with just 10 samplesYC S23San FranciscoStartup →AICedanaFast, reliable, reproducible AI with GPU live migrationYC S23New York CityStartup →AIInactiveCodeStoryAide is an AI-native , privacy-first IDE built on top of VSCodeYC S23LondonStartup →AICognitio LabsAI back office for food product quality teamsYC S23Los AngelesStartup →AIAcquiredContinuePioneering open-source coding agentYC S23San FranciscoStartup →
Company
AtlaThe improvement engine for AI agentsteam of 10InactiveAI, Data, Devtools
AutomorphicInfuse knowledge into language models with just 10 samplesteam of 3ActiveAI, Devtools
CedanaFast, reliable, reproducible AI with GPU live migrationteam of 5hiringActiveAI, Devtools
CodeStoryAide is an AI-native , privacy-first IDE built on top of VSCodeteam of 4InactiveAI, Devtools
Cognitio LabsAI back office for food product quality teamsteam of 3ActiveAI, Data
ContinuePioneering open-source coding agentacquired by Cursoron 3 Glyph sourcesAcquiredAI, Devtools

About Chatter

Chatter is Postman for LLMs. Our platform helps companies and developers test their LLM models. Iterate on prompts, run them across model families and evaluate them against test cases – all in one place. With collaboration features, engineers can design LLM chains while QA can write test cases.

YC batch
S23 · Summer 2023
Status, per YC
Acquired
Category
AI, Developer tools
Team size
2
Location
Philadelphia, PA, USA
Checked
6h ago

YC tags: AIOps, Developer Tools, Generative AI, SaaS

Chatter in S23: 220 companies, 78% AI

Chatter: questions

Which YC batch was Chatter in?

Chatter was in Y Combinator's Summer 2023 batch (S23).

Is Chatter still active?

Y Combinator lists Chatter as acquired.

Where is Chatter based?

Chatter lists Philadelphia, PA, USA as its location on YC's directory.