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Best API Monitoring Tools in 2026

Keeping tabs on API behavior means looking beyond whether an endpoint responds: the frequency and location of checks, and what happens when they fail, can all matter. Compare check frequency, response assertions, and multi-region checks alongside monitor limits and private locations. Incident workflows, free-plan availability, and paid-from pricing round out the comparison. Site24x7 API Monitoring, APIContext, and Dotcom-Monitor are among the entries, with Postman and Tallwatch also shown. Use the listed criteria to consider where monitoring should run, what checks matter to you, and how a team can handle an incident.

  1. 1

    APIContext

    Free plan LinuxMacWeb+1

    APIContext combines scheduled checks with contract, telemetry, and security validation. Its free tier has a defined test allowance and does not include simulated browser journeys.

    7.7 Free plan · paid from $29/mo (annual) · 14-day trial Visit site
  2. 2

    Checkly

    Free plan APILinuxWeb

    Checkly combines uptime monitors, browser-based checks, and scheduled Playwright suites with a code-oriented workflow.

    7.5 Free plan · paid from $24/mo Visit site
  3. 3

    Dotcom-Monitor

    by Dotcom-Monitor
    Free plan AndroidAPIiPhone+4

    Dotcom-Monitor offers target monitoring with multiple alert routes and plan limits that vary by tier.

    7.5 Free plan · paid from $13.33/mo · 30-day trial Visit site
  4. 4

    Loadster Synthetic Monitoring

    Free plan APIExtensionLinux+4

    Loadster combines scripted monitoring, diagnostics, alerts, and status pages, with options for public or self-hosted checks.

    7.5 From $29/mo Visit site
  5. 5

    CyberPing

    Free plan APISelf-hostedWeb

    Pick CyberPing if you need API performance monitoring with regional checks, latency analytics, or alert routing.

    7.4 Free plan · paid from $49/mo · 14-day trial Visit site
  6. 6

    ObserveOne API Monitoring

    Free plan APIExtensionSelf-hosted+1

    ObserveOne combines configurable API checks with multiple alert destinations, automation interfaces, and self-hosting options.

    7.4 Free plan · paid from $6/mo (annual) Visit site
  7. 7

    Assertible

    Free plan APIWeb

    Choose Assertible if you need HTTP service checks, deployment smoke tests, or API test synchronization with common specification formats and Postman collections.

    7.3 Free plan · paid from $25/mo Visit site
  8. 8

    Postman

    by Postman
    Free plan ExtensionLinuxMac+2

    Postman combines API creation, testing, documentation, and monitoring in one platform, with a free plan and paid options. Check plan availability and the annual billing terms before choosing a tier.

    7.3 Free plan · paid from $9/mo (annual) Visit site
  9. 9

    Runscope

    Free plan APILinuxMac+3

    Pick Runscope for sequential API tests with detailed assertions, multi-region checks, private locations, and CI/CD use.

    7.3 From $79/mo Visit site
  10. 10

    HostTracker

    Free plan APIWeb

    HostTracker combines external monitoring, rechecks, alerts, and status pages with a broad set of developer integrations.

    7.2 Free plan · paid from $5/mo · 30-day trial Visit site
  11. 11

    Sentinel

    Free plan APIExtensionMac+1

    Choose Sentinel if you need multi-region website and infrastructure monitoring with broad checks, alerts, and status pages.

    7.2 Free plan · paid from $12/mo · 14-day trial Visit site
  12. 12

    PageLantern

    Free plan APIWeb

    Choose PageLantern if you need externally configured monitoring across websites, APIs, DNS, or scheduled jobs, with alert channels and hosted status pages.

    7.1 Free plan · paid from $7/mo (annual) Visit site
  13. 13

    Site24x7 API Monitoring

    Free plan AndroidAPIiPhone+4

    Site24x7 API Monitoring offers protocol coverage, REST response validation, and multi-step transaction checks.

    7.1 Free plan · paid from $9/mo (annual) · 30-day trial Visit site
  14. 14

    Tallwatch

    Free plan APILinuxMac+2

    Tallwatch combines multi-region checks with alert routing, on-call features, and status pages.

    7.1 Free plan · paid from $11.99/mo (annual) Visit site
  15. 15

    pingdan

    Free plan Web

    pingdan offers broad HTTP assertions, frequent checks, certificate warnings, and many alert destinations at no listed cost.

    6.9 Free plan Visit site
  16. 16

    Signalog

    Free plan APIWeb

    Choose Signalog if you want monitoring, incident coordination, paging, and status pages together, with integrations for alert delivery and event ingestion.

    6.9 Free plan · paid from $19/mo Visit site
  17. 17

    Sysmos

    Free plan APILinuxWeb

    Choose Sysmos if you want API health checks, Linux observability, and alert routing in one monitoring service.

    6.9 Free plan · paid from $29/mo · 14-day trial Visit site
  18. 18

    Watchlog

    Free plan APILinuxSelf-hosted+2

    Watchlog covers infrastructure, logs, traces, real-user monitoring, synthetic journeys, and API checks in one platform. Its free plan is limited, and Pro usage can incur additional charges.

    6.9 Free plan · paid from $4.99/mo · 30-day trial Visit site
  19. 19

    Status Inspector

    Free plan APIWeb

    Status Inspector combines multiple monitor types, detailed API assertions, alerts, and public status pages.

    6.8 Free plan Visit site
  20. 20

    Uptara

    Free plan APIWeb

    Choose Uptara if your team needs API monitoring with multi-region failure checks, synthetic workflows, and SLA tracking.

    6.7 Free plan · paid from $15/mo · 14-day trial Visit site
  21. 21

    UptimeRobot

    by UptimeRobot
    Free plan AndroidiPhone

    UptimeRobot offers availability monitoring, multiple alert channels, and status pages, with a free tier and paid options.

    6.7 Free plan · paid from $12/mo (annual) Visit site
  22. 22

    Sematext Synthetics

    Free trial APILinuxSelf-hosted+2

    Sematext Synthetics covers both endpoint checks and scripted browser journeys, with certificate monitoring and private-location agents.

    6.1 From $2/mo · 14-day trial Visit site
  23. 23

    Apica Vanguard

    Paid Self-hostedWeb

    Apica Vanguard combines synthetic monitoring with checks for AI agent workflows and links failures to infrastructure signals. Buyers need to contact Apica for pricing and a demo.

    5.8 Pricing on request Visit site
  24. 24

    Oh Dear

    by Oh Dear
    Free trial Web

    Oh Dear combines frequent checks across multiple monitoring areas with a broad set of alert channels.

    5.8 From €15/mo · 10-day trial Visit site
  25. 25

    Uptrends

    by Uptrends
    Free trial AndroidAPIiPhone+3

    Choose Uptrends if you need website, application, API, or server monitoring with flexible alert channels and regional synthetic checks.

    5.8 From $42/mo (annual) · 30-day trial Visit site

#1Places #1, #2, #3, #4, #5 on this list can be bought by the makers of the software on it. See the price

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