Zapier vs Relay.app vs Windmill vs Stack AI

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

Your tool
Zapier
vs
Competitor 1
Relay.app
Competitor 2
Windmill
Competitor 3
Stack AI
Compare
4 tools · best value per row highlighted
Your tool Zapier
zapier.com
Connect your apps without writing code
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Competitor Relay.app
relay.app
Relay.app is a platform to create AI Agents that work for you across Gmail, Notion, Salesforce, HubSpot, and 100+ other apps. Agents created in Relay.app are *actually* useful, as they're easy to cre
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Competitor Windmill
windmill.dev
Windmill is an open-source, code-first orchestration platform for internal software.
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Competitor Stack AI
stack-ai.com
Connect AI models visually
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Traffic estimated monthly website traffic
Monthly visits
5.3Mvisits/mo
158.1Kvisits/mo
—
6.3Kvisits/mo
MoM change
▼ 5.9%
▼ 32.7%
—
▼ 57.9%
6-month growth
-26.7%
-30.9%
—
-93.7%
Global rank web
#6,051
#182,862
—
#1,700,092
Avg. last 3 months
5.5M
187.1K
—
13.9K
Bounce rate lower is better
38%
38%
—
39%
Pages / visit
10.2
2.8
—
1.8
Visit duration
6m 43s
1m 15s
—
14s
Traffic sources
● Direct 81% · ● Referral 12%
● Direct 93% · ● Referral 4%
—
—
ZapierRelay.appWindmillStack AI
01.8M3.6M5.5M7.3MZapier · 6.3MZapier · 5.9MZapier · 6.8MZapier · 6.5MZapier · 7.3MZapier · 6.6MZapier · 6MZapier · 5.5MZapier · 5.7MZapier · 5.3MRelay.app · 216.8KRelay.app · 241.7KRelay.app · 272KRelay.app · 229.9KRelay.app · 228.8KRelay.app · 251.1KRelay.app · 193.9KRelay.app · 168.4KRelay.app · 234.9KRelay.app · 158.1KStack 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 · 6.3K1K10K100K1M10MZapier · 6.3MZapier · 5.9MZapier · 6.8MZapier · 6.5MZapier · 7.3MZapier · 6.6MZapier · 6MZapier · 5.5MZapier · 5.7MZapier · 5.3MRelay.app · 216.8KRelay.app · 241.7KRelay.app · 272KRelay.app · 229.9KRelay.app · 228.8KRelay.app · 251.1KRelay.app · 193.9KRelay.app · 168.4KRelay.app · 234.9KRelay.app · 158.1KStack 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
Freemium
Freemium
Starting price
$19.99per month · free tier available
$19per month · free tier available
$120per month · free tier available
Free tier
Free tier
Free trial
–
API access
–
–
Plans
Free FreeProfessional $19.99/moTeam $69/moEnterprise Custom
—
Free and Open-source (self-host) FreeEnterprise $120/mo
—
Capabilities input → output
Input
Text
Text
Code
DataDocumentsText
Output
Apps
Apps
Apps
Apps
Skill level
Intermediate
Advanced
Advanced
Intermediate
Categories
Development & CodeProductivity & OfficeAI AgentAI Workflow+1 more
Productivity & OfficeAI AgentAI Workflow
Development & CodeProductivity & OfficeAI Developer ToolsAI Workflow+1 more
Development & CodeProductivity & OfficeAI AgentAI Workflow+1 more
Tasks what each tool can do · 1 shared · core   partial
Tasks covered
6
6
4
5
Workflows
Agents
–
No-code
–
–
Agent creation
–
–
Automation
–
–
–
Self hosted
–
–
–
Business automation
–
–
–
Developer tools
–
–
–
Finance workflow automation
–
–
–
Lead generation
–
–
–
Lead management
–
–
–
Process automation
–
–
–
Productivity
–
–
–
Workflow deployment
–
–
–
Community on aitoolstime
Rating
no ratings yet
no ratings yet
no ratings yet
no ratings yet
Upvotes
▲ 1
▲ 0
▲ 0
▲ 0
Saves
0
0
0
0
Reviews
0
0
0
0
Prompts
0
0
0
0
Verified listing
–
–
–
–

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.