Vapi vs Stack AI vs Haystack

Which one fits you in 2026? Traffic, pricing, input → output, tasks and community side by side.

Your tool
Vapi
vs
Competitor 1
Stack AI
Competitor 2
Haystack
Competitor 3
Suggested competitors for Vapi: Retell AI97% ElevenLabs Conversational AI93% Synthflow93% VVoicePod92% CloudTalk | AI Voice Agents90% Goodcall88% BlandAI88% PolyAI87%
Compare
3 tools · best value per row highlighted
Your tool Vapi
vapi.ai
Vapi is a developer platform for building, testing and deploying voice AI agents that talk to customers on the phone.
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Competitor Stack AI
stack-ai.com
Connect AI models visually
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Competitor Haystack
haystack.deepset.ai
Haystack is an open-source AI orchestration framework from deepset for building production-grade LLM applications and agents.
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Traffic estimated monthly website traffic
Monthly visits
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6.3Kvisits/mo
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MoM change
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▼ 57.9%
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6-month growth
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-93.7%
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Global rank web
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#1,700,092
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Avg. last 3 months
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13.9K
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Bounce rate lower is better
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39%
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Pages / visit
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1.8
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Visit duration
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14s
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Traffic sources
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VapiStack AIHaystack
042K84K126K167.9KStack AI · 143.4KStack AI · 153.7KStack AI · 167.9KStack AI · 160KStack AI · 99.4KStack AI · 35.9KStack AI · 17.4KStack AI · 20.6KStack AI · 14.9KStack AI · 6.3K1K10K100K1MStack AI · 143.4KStack AI · 153.7KStack AI · 167.9KStack AI · 160KStack AI · 99.4KStack AI · 35.9KStack AI · 17.4KStack AI · 20.6KStack AI · 14.9KStack AI · 6.3KNov '25DecJan '26FebMarAprMayJunJulAug
Pricing
Model
Freemium
Freemium
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Starting price
$29per month
Free tier
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Free tier
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Free trial
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API access
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Plans
No Success Package FreeCore $29/moPro $999/moPremier Custom
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Capabilities input → output
Input
AudioText
DataDocumentsText
CodeDocuments
Output
AppsAudio
Apps
Apps
Skill level
Advanced
Intermediate
Advanced
Categories
Business & MarketingVoice & SpeechAI Call CenterAI Customer Service+1 more
Development & CodeProductivity & OfficeAI AgentAI Workflow+1 more
Development & CodeProductivity & OfficeAI AgentAI Developer Tools
Tasks what each tool can do · 0 shared · core   partial
Tasks covered
7
7
5
Agents
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Agent creation
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LLM development
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No-code
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Voice agents
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Workflows
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Business automation
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Call agents
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Call center automation
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Customer calls
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Customer support
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Developer tools
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Process automation
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Agent memory
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Call answering
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Calls
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Finance workflow automation
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Community on aitoolstime
Rating
no ratings yet
no ratings yet
no ratings yet
Upvotes
▲ 0
▲ 0
▲ 0
Saves
0
0
0
Reviews
0
0
0
Prompts
0
0
0
Verified listing
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Traffic figures are third-party estimates for the tool's own domain; tools sharing a domain with a bigger product are not counted. Pricing is captured from each tool's site and may lag.