10 Best API Monitoring Tools in 2024 (And 3 Open-source Options)

200,000,000. That’s how many APIs DevOps.com estimated to be in use both publicly and privately back in 2021.

Fast forward a bit, and 70% of developers believe that they will increase their API usage even further. There was even a study done by Cloudflare back in 2021 which concluded that 54% of all requests processed by them were API calls. Check out the chart below:

We’re talking about huge numbers! Hundreds of millions, if not, billions at this point. And since Cloudflare manages an unfathomable amount of traffic, it’s not unreasonable to say that more than half of all online traffic is run through APIs. In fact, Zipdo estimates that APIs constitute a mind-boggling 83% of all web traffic.

With numbers like that, it’s very clear that your APIs need to be monitored just as often as your regular web pages. Picking the right tool for such an important job might seem a little daunting, especially in an ocean of options.

But don’t panic. Later, we’ll deep dive into a comprehensive list of 10 of the best API monitoring tools that you can sign up for right now.

❗ New to API monitoring? Explore the basics in: What is API monitoring?

Top 10 API Monitoring Tools in 2024

Now it’s time to take a closer look at the Best API Monitoring Tools in 2024.

1. Better Stack

Better Stack offers API monitoring as a part of its complex Uptime Monitoring and Incident management solution.

It offers a radically better monitoring solution covering all the important aspects of synthetic monitoring, such as HTTPs keyword checks, Heartbeat, SSL, Ping, TLD, TCP/UDP, POP3/IMAP/SMTP, and DNS server monitoring. Your website is monitored as often as every 30 seconds from multiple locations to prevent false alerts, and you can also set geo-specific checks to focus on location-related issues.

Better Stack also offers integrations with the most popular third-party tools and platforms such as Heroku, Datadog, New Relic, Grafana On-Call, PagerDuty, Opsgenie, AWS CloudWatch, or Google Cloud.

Each incident is documented with a screenshot and an error log, a second by second incident timeline, post-mortem, and advanced incident escalation rules. You can benefit from its on-call scheduling and integrations to plan in advance and always have first-responders on the line. In case of any downtime, you can create custom status pages with customizable designs that your users can subscribe to.

🌟 Key features

• Uptime monitoring
• API monitoring
• Log management
• Incident management
• Comprehensive observability dashboards

➕ Pros

• 30-second check frequency
• Incident Management and Status Pages built-in
• On-call scheduling
• Dozens of integrations with popular third-party platforms

➖ Cons

• Not considered a full-stack observability solution
• Not yet as feature-rich as some of the larger, much older platforms in the space

💲 Pricing

Better Stack Uptime is available for free in a basic monitoring and incident management package.

The Logs premium packages start at just $25/month and come with a 30GB allowance and 15 days of retention.

Uptime premium packages also start at just $25/month and come with 50 monitors, 5 status pages, and built-in incident management.

Want to see more? You can check out our full range of packages by visiting the pricing page.

2. Datadog

With Datadog's Proactive API monitoring, you can automate site availability monitoring and reduce mean time to getting to the root cause. Datadog allows you to validate all layers of your systems (from HTTP to DNS) from several geolocations, and you can focus especially on areas that are essential to your business by creating custom locations.

Datadog users can create end-to-end tests with a codeless web recorder. This enables you to click through your applications just like a real user would and test the API in real-time. On top of that, you can get a clear view of the root cause with helpful test components like screenshots, page performance data, backend traces, errors, and other resources.

You can even compare application performance from both behind the firewall and outside it. Datadog also emphasizes the importance of time management with proper tools maintaining and test automatization. Thanks to the wide range of monitoring solutions, you can resolve any issues and achieve Full Stack Visibility.

Keep in mind, though, that Datadog’s biggest complaint topic on G2 is that it’s expensive, and not really aimed at small-to-medium sized businesses. We’ll dig into the pricing a little more in just a bit.

🌟 Key features

• Synthetic monitoring
• Infrastructure monitoring
• Log management
• Real user monitoring
• APM
• SIEM

➕ Pros

• Full-stack observability
• Hundreds of integrations
• 20+ individual solutions

➖ Cons

• Expensive at any scale
• Not designed for small businesses

💲 Pricing

With 20+ individual solutions, it can be tough to summarize Datadog’s pricing scheme. However, there are a few tools that we will mention here, just to give you an idea of the costs associated with the platform.

• Infrastructure monitoring starts $15 per host per month
• Log management starts at $0.10 per ingested GB and $1.70 per million log events per month
• Synthetic monitoring starts at $5 per 10,000 API runs and $12 per 1,000 browser runs
• Real user monitoring (RUM) starts at $1.50 per 1,000 sessions per month
• APM starts at $31 per host per month
• SIEM starts at $5 per million analyzed events

3. Assertible

Assertible is a comprehensive API monitoring tool, claiming to be the easiest way to monitor your API. They support that claim by offering custom API tests using industry-standard patterns for data validation, functional test cases, and synthetic monitoring.

One of the features that makes Assertible’s API tests so helpful is that they stay up to date without any interaction needed from the user. As specifications are updated, you can add updated responses, parameters, and headers, click sync, and know that all API tests will be synced.

On top of that, they offer Collaborative API monitoring, where you can invite your whole team to participate in diagnostics. All of this is possible without any coding, thanks to their built-in assertions and single-click monitoring.

🌟 Key features

• API monitoring

➕ Pros

• Multi-environment testing
• Post-deploy smoke tests
• Powerful HTTP assertions

➖ Cons

• Zero reviews online

💲 Pricing

You can get Assertible for free and get 10 tests for 2 services and 1000 test results retention. Their first paid plan - Standard allows you to monitor 25 services, 500 tests per service, and 5k test results retention, for $25/month. The higher-tier plans - Startup and Business offer you up to 50 web services and 1000 tests per service, 10,000 results retention, and 20 team members.

4. Dotcom-monitor

Dotcom-monitor's Web API monitoring allows you to monitor your APIs and uptime for SOAP, REST, JSON, and XML web services. Dotcom-monitor also offers a Postman integration, allowing you to use a collection of integration tests for internal API testing. This is ensured by a shared public link to the Dotcom-Monitor platform.

Dotcom-monitor’s API monitoring solution is simple, but still very effective. With the ability to monitor for 30 global locations, users can set up multi-step API calls to verify more complex API sequences.

🌟 Key features

• API monitoring
• Infrastructure monitoring
• Web application monitoring

➕ Pros

• Comprehensive dashboards and real-time data
• Load testing
• Multi-location testing

➖ Cons

• Price per monitor is expensive
• User reviews indicate reporting complexities
• User reviews indicate some difficulties setting up more complex workflows

💲 Pricing

Dotcom-Monitor offers Web API monitoring in the Web Services package starting at $19.95/month. The pricing from there depends on check frequency and tasks frequency, in either 5 minutes Premium or 1 minute Platinum package.

5. API Science

API science offers an API-centric, monitoring and testing platform scalable from small businesses all the way to enterprises. Their Advanced API is based on Multi-step and JavaScript, allowing you to test real CRUD sequences, beyond GET calls.

With API Science you can also monitor external APIs down the supply chain to make sure your partners are meeting their SLAs, if they lack anything, and their overall performance. Their comprehensive reporting helps you to spot any developments and trends to avoid any sudden shifts or failures. Their Full-featured API allows you to monitor all the APIs, with their very own API.

It’s important to note that API Science was acquired by APImetrics. It is likely that a lot of their offerings, solutions, and features will change, but we can still expect the core of what API Science was/is to remain similar, if not identical.

🌟 Key features

• API monitoring

➕ Pros

• Intelligent API diagnostics
• 60 seconds testing interval
• Customized reporting
• Test scripting capabilities

➖ Cons

• Zero reviews online

💲 Pricing

Prices for API Science start at $29/month in the BASIC package. This allows for 3 Users and 100,000 API calls. Depending on your needs, you can get packages all the way up to 500,000 API calls, but it will cost you $499/month.

6. Saucelabs

APIFortress is a cloud-native REST and SOAP web services monitoring platform integrated into Saucelabs. You can create and edit your tests using their IDE Forge or a drag-and-drop GUI. Scheduling is handled by API Fortress' built-in scheduler allowing you to schedule tests to act as uptime, functional uptime, and performance monitors. Tests can be run in sets, by tag, individually or all together.

Functional Uptime monitoring allows you to check beyond the simple HTTP 200 OK response. Metrics visualization is handled by Kibana. To gain an overall idea of your infrastructure state, API Fortress automatically generates a real-time status page that collects insights about API performance for you and your team.

What’s more is that SauceLabs allows users to automate and scale API testing by connecting to an onboard test scheduler or to any CI/CD platform. You can debug within SauceLabs or connect to a notifications/events manager platform like PagerDuty.

🌟 Key features

• API monitoring
• Crash and error reporting
• Mobile app testing

➕ Pros

• Multiple deployment options
• Helpful Kibana visualization
• Multiple configuration options for numerous OS combinations

➖ Cons

• Lacks some valuable test analytics
• User reviews indicate slow load times and latency

💲 Pricing

Sauce Labs offers 3 different solutions, each with a multitude of pricing options that all depend on the number of parallel tests you want.

Live Testing starts at $39/month but can go all the way up to $769/month if you want more tests. Virtual Cloud starts at $149/month and can go up to $3599/month with more tests. Finally, Real Device Cloud starts at $199/month but goes up to $4799/month with the maximum number of tests added.

7. RapidAPI

RapidAPI testing offers functional API testing and monitoring, supporting any API type. It allows you to centralize and monitor worldwide operations under one roof and improve efficiency by CI/CD integration.

One of the most interesting features must be RapidApiHub and Enterprise Hub, offering thousands of curated and tested APIs devised into categories according to use. RadidAPI's option to build functional test flows that deeply verify the state of REST, SOAP, and GraphQL APIs.

What’s interesting about RapidAPI are the numbers that surround it. 4,000,000 developers actively use it to design, publish, consume, and share APIs. With over 40,000 APIs currently in the HUB, RapidAPI is responsible for over 1 trillion API calls each and every month.

🌟 Key features

• API testing and monitoring

➕ Pros

• Extensive API hub
• Reliable API monitoring capabilities

➖ Cons

• User reviews indicate poor support
• User reviews express some security concerns with using APIs from the API hub
• Poor documentation and difficult to get help

💲 Pricing

You can get RapidAPI for free, with 2 tests per API, 2000 API calls/month, and e-mail only notifications. If you’re wanting to up the ante to the Business plan, it will cost you a staggering $1999/month minimum. It does, however, come with unlimited test calls and numerous additional developer assets.

8. Sematext Synthetics

Sematext Synthetics offers you a complex solution to both API and website monitoring. Their solution is built for modern monitoring needs, including hybrid environments, cloud, and on-premise servers. With Synthetics, you can monitor a wide array of metrics.

Synthetics offers Uptime and API monitoring, from multiple locations, from private networks, and behind firewalls, across all layers (DNS, TCP, SSL, and HTTP) and customizable API monitoring. Apart from that, Synthetics will keep an eye on SSL certificates, Website performance, or End-to-End visibility.

Because of the single-pane approach, Sematext promises to help users correlate data from across infrastructure metrics, application logs, events, real-user data, and synthetic performance metrics.

🌟 Key features

• Synthetic monitoring
• Real user monitoring
• Log management
• Infrastructure monitoring

➕ Pros

• Full-stack monitoring
• Out-of-the-box dashboards
• Helpful support
• Price-per-monitor option

➖ Cons

• Log monitoring can be expensive
• Dashboard configurations can be a bit overwhelming
• User reviews indicate difficulties with user management
• Lacks some helpful integrations with security tools

💲 Pricing

Sematext has adapted both the pay-as-you-go pricing model - you build your own subscription according to your needs; and the standard subscription packages. The pay-as-you-go Synthetics starts at $2/monitor and $7/Browser monitor. Their starter package for Synthetics is Standard starting at $29/month with 40 HTTP and 5 Browser maximum with 30 days of data retention.

9. Postman

Postman gives you a free hand when it comes to API testing. Their platform allows you to monitor a broad spectrum of APIs ranging from REST and SOAP through GraphQL, OpenAPI, RAML, Swagger, all the way to JSON, cURL, and WADL.

Postman uses Newman - a command-line Collection Runner that enables you to run and test a Postman Collection directly from the command line. On top of that allows you to automate your API testing or write your own operation-specific tests.

The platform includes an impressive list of comprehensive tools to help you design, test, document, mock, and share your own APIs. It’s an ecosystem that promotes collaboration between developers for higher-quality APIs.

🌟 Key features

• API monitoring
• API repository

➕ Pros

• Great support for REST and SOAP APIs
• Very user-focused UI
• Fairly large community of users

➖ Cons

• Steep learning curve
• Limited documentation
• Limited design frameworks
• User reviews indicate heavy disk usage for desktop version

💲 Pricing

Postman is available for free, with a maximum of 1000 calls to Postman API, Mock server calls, and monitoring API calls. Their first paid subscription starts at $14/month in the Basic package, offering you 10 integrations, 10,000 calls to Postman API, Mock server calls, and Monitoring API calls. You can upgrade to the Professional plan for $29/month, and it comes with 100,000 calls to Postman API, mock server calls, and Monitoring API calls as well as access to 50 integrations.

They also have an Enterprise plan which can be completely customized based on your needs. This plan will give you full access to all 100 integrations as well as give you access to all sorts of API development assets.

10. Dynatrace

Last on this list, we have Dynatrace. Dynatrace is a full-stack observability solution with lots of capabilities, including synthetics. It is very much an enterprise tool, but it does perform well in terms of API monitoring.

Dynatrace allows users to automatically find and fix issues before they impact the end user. Through their comprehensive application availability and performance testing, users can pinpoint the root cause of incidents within their applications and fix/optimize them relatively quickly.

Dynatrace has thousands of test locations all around the world. This allows you to continuously check the performance of your APIs and ensure that they’re working properly proactively.

🌟 Key features

• Full-stack monitoring
• Infrastructure monitoring
• Synthetic monitoring
• Real user monitoring
• App security
• Log management and analytics

➕ Pros

• Feature-rich toolset
• Prices based on data usage
• Powerful alerting capabilities
• Utilizes AI

➖ Cons

• User reviews indicate extreme expenses at scale
• User reviews indicate difficulties with data collection
• User reviews indicate difficulties with the debugging tool

💲 Pricing

As mentioned just above, Dynatrace pricing is based on data usage. Instead of charging per-monitor for synthetics, you get charged based on the number of synthetic requests.

You’ll end up paying $0.001 per request, which seems relatively small. But if you break it down a little bit, it ends up being pretty expensive at scale. If you run 2 minute intervals from a single location, you’ll end up running 30 requests per hour. Multiply that by 24 hours in a day, you get 720 requests every day. If you multiply that by the average number of days in a month, 30, you’re running 21,600 requests per month.

21,600 * 0.001 = $21.6 per monitor! The shorter your intervals, the more expensive each monitor will get.

Comparing the 10 Best API Monitoring Tools

Top 3 open-source API monitoring tools

Open-source tools aren’t for everyone, but they do offer a few good options for API monitoring. Bear in mind that these tools require hosting, management, and maintenance by the user. Although they are free initially, they will inevitably come with a cost of ownership that will be impossible to calculate from anyone’s perspective aside from your own.

But, don’t let that scare you too much. If you’re up for the challenge, here are the top 3 open-source API monitoring tools.

1. Prometheus

As a metric-based solution, Prometheus is designed to track the performance, health, and even behavior of the user’s organization, including their APIs. It sends alerts based on the real-time metrics that it collects and stores.

Prometheus uses a very functional query language called PromQL. This language allows users to both select and aggregate time series data in real-time. The result can then be expressed in graphs or tabular data.

What’s unique about Prometheus is that external systems can consume the HTTP API. In other words, Prometheus integrates with tools like Better Stack, and even has out-of-the-box support from Grafana. In fact, you can create dashboards in Grafana that display metrics collected by Prometheus.

🌟 Key features

• Open-source monitoring

➕ Pros

• Easy integration with 3rd party tools
• Single web portal
• Large number of visualization tools

➖ Cons

• Cost of ownership can be pricey
• User reviews indicate some difficulty in learning PromQL
• User reviews indicate some complications with query

Read more about Prometheus:

• How to Visualize Prometheus Metrics with Grafana
• How to Monitor Linux Servers with Prometheus and Node Exporter
• Prometheus vs Grafana

2. Graphite

Graphite has 3 main components: Graphite, Carbon, and Whisper. Graphite web is used to render graphs, Carbon is used to listen for time series data, and Whisper is used for storing said time series data.

One of the downfalls of Graphite is that their UI is not all that grand. Luckily, though, they integrate with grafana for better visualizations. Graphite itself is not a data collection tool. Instead, apps need to be configured to send data to Graphite, which then uses Carbon to listen for data. Carbon will then send the data to Whisper, which stores it in time series data on a filesystem.

This open-source system can work together to give you valuable insight into basically any app, process, or service, including APIs.

🌟 Key features

• Open-source monitoring

➕ Pros

• Simple metric storage and visualization

➖ Cons

• Needs to be integrated with Grafana for decent visualizations
• Apps need to be configured to send data to Graphite

3. Signoz

Signoz is known as a full-stack and open-source APM that can be utilized for API monitoring. It’s built to natively support OpenTelemetry, which has become a well known standard for instrumenting applications that are cloud-native.

Signoz is decently suited for monitoring APIs that are based on serverless architecture or microservices. Using it, you can monitor the endpoints of your services and get valuable insights on metrics like P95 and P99 latencies.

🌟 Key features

• Open-source monitoring

➕ Pros

• Out-of-the-box visualizations and dashboards
• Easy to configure
• Helpful community

➖ Cons

• Very few reviews online
• Limited feature set
• User reviews indicate some issues with log-based alerting

Conclusion

There you have it, the 10 best API monitoring tools. There are lots of factors to consider when choosing your own API monitoring tool, and everyone’s needs are slightly different. The best advice anyone can give you in this situation is to take your time, do your research, and sign up for as many free trials as you can.