Side by side
Assertible vs Sentinel
Both stand on api monitoring tools. Which one you can start free with, which one lets you read the code, and what each costs once you pay.
Choose Assertible if you need HTTP service checks, deployment smoke tests, or API test synchronization with common specification formats and Postman collections. Look elsewhere if the Personal plan's service, test, result, or team limits do not fit; paid plans start at $25 a month.
Visit AssertibleChoose Sentinel if you need multi-region website and infrastructure monitoring with broad checks, alerts, and status pages. The Free plan covers up to 10 monitors, while paid monthly plans add capacity and features; check the plan limits that fit your monitor and status-page needs.
Visit SentinelThe facts
| Assertible | Sentinel | |
|---|---|---|
| Free plan | Yes | Yes |
| Open source | Not published | No |
| Runs on | API, Web | API, Extension, Mac, Web |
| Lowest paid plan | Standard: $25 a month | Starter: $14 a month |
| Plans published | 4 | 4 |
| Maker | Not published | Not published |
| Website | assertible.com | sentinel.rootstuff.io |
| On api monitoring tools | #7 of 27 | #11 of 27 |
Assertible: what it does well
- Creates HTTP assertions and shows request details and results.
- Runs smoke tests automatically after deployment to staging or production.
- Imports and syncs tests with OpenAPI, Swagger, and Postman.
- Integrates with GitHub, Slack, PagerDuty, and Zapier.
- Free tier can be used indefinitely.
What to know first
- The free Personal plan allows two web services and 10 tests per service.
- Personal retains 1,000 results and supports one to two members.
- Shorter monitoring intervals are available on paid plans.
- Paid plans start at $25 a month.
Sentinel: what it does well
- Checks cover uptime, certificates, DNS, domains, page keywords, APIs, ports, and jobs.
- Checks run from four regions as often as every 30 seconds.
- Alerts reach email, SMS, Slack, Discord, Telegram, Teams, or webhooks.
- Customizable status pages include incident history.
- MCP access lets compatible AI agents query monitors and assist with incident triage.
What to know first
- Free checks run every five minutes and cover up to 10 monitors.
- Free includes one public status page.
- The macOS app requires macOS 13.0 or later and a read-only API token.
Alternatives to Assertible Alternatives to Sentinel The whole list