kitio.aiAlumnium vs CARBON by testers.ai
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Alumnium is completely free, while CARBON by testers.ai is freemium.
At a glance
Best for
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Plain-language test steps
- Selenium, Playwright and Appium
- MCP server for coding agents
- TypeScript, Python and Java clients
- Choice of AI provider
- 12 free testing commands
- Exploratory and risk-based testing
- Accessibility checks
- Evidence-backed findings
- MCP server
- Regression test building
| Feature | Alumnium | CARBON by testers.ai |
|---|---|---|
| Best for | Open-source AI test harness for web and mobile apps, with MCP | Open-source AI test manager that runs inside your coding agent |
| Category | Coding | Coding |
| Pricing model | Free | Freemium |
| Starting price | Free | $49/mo |
| Free plan | Yes, fully free | Yes |
| Made by | Alumnium | testers.ai |
| Based in | – | – |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
Alumnium is completely free, while CARBON by testers.ai is freemium.
Free plan
Cheapest paid plan
Top plan
Free trial
4 plans
Core
Free
- MIT open source
- 12 testing commands
- Accessibility and exploration
Pro
$49/mo
- Deeper testing workflows
- Everything in Core
Team
$95/mo
- Per user
- Minimum 5 developers
- Email support
Enterprise
$195/mo
- Per user
- Minimum 5 developers
- Zoom support and customizations
Prices in USD, checked Nov 5, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
Alumnium
- Free and MIT licensed
- Builds on drivers you already use
- Lets coding agents test their own changes
- Needs your own model API key
- Each test run adds model API costs
- Still pre-1.0
CARBON by testers.ai
- Core edition is free and MIT licensed
- Works inside agents you already use
- Broad framework and tracker support
- Needs a coding agent to run
- Team plans require at least 5 developers
- Requires Node.js 22+ for MCP setup
Which one should you choose?
Choose Alumnium if you want:
- Free and MIT licensed
- Builds on drivers you already use
- Lets coding agents test their own changes
Watch out: needs your own model api key.
Choose CARBON by testers.ai if you want:
- Core edition is free and MIT licensed
- Works inside agents you already use
- Broad framework and tracker support
Watch out: needs a coding agent to run.
Alumnium vs CARBON by testers.ai FAQ
What is the difference between Alumnium and CARBON by testers.ai?
Alumnium: Open-source AI test harness for web and mobile apps, with MCP. CARBON by testers.ai: Open-source AI test manager that runs inside your coding agent. Both are coding tools.
Is Alumnium or CARBON by testers.ai cheaper?
Alumnium is completely free, while CARBON by testers.ai is freemium.
Do Alumnium and CARBON by testers.ai have free plans?
Alumnium: Yes, fully free. CARBON by testers.ai: Yes.
Who makes Alumnium?
Alumnium is made by Alumnium.
Who makes CARBON by testers.ai?
CARBON by testers.ai is made by testers.ai.
Which should I choose, Alumnium or CARBON by testers.ai?
Choose Alumnium if you value free and mit licensed and builds on drivers you already use. Choose CARBON by testers.ai if you value core edition is free and mit licensed and works inside agents you already use.