How much time does the browser add to a task?
A session creation number measures one API operation. A usable browser also needs a connection and a navigation, and a long-running workflow pays for many actions after startup. Compare lifecycle latency and running-task throughput separately.
A workflow with one navigation and a hundred browser actions may favor a different execution path than a workload that opens and closes a browser for every action. Test both shapes before making a platform-wide speed claim.
Compare the browser lifecycle
Kernel: Kernel exposes browser creation and control APIs. Its documentation distinguishes on-demand browsers from configured browser pools, so compare the acquisition path your application will actually use.
AWS AgentCore Browser: Create or select a Browser Tool, then start an isolated browser session. The documented default session timeout is 15 minutes and the maximum is eight hours. Browser automation uses the session's WebSocket endpoints.
Compare the evidence from a run
Kernel: Live browser URLs support an embedded view and a read-only option. Replays and browser telemetry are separate observability surfaces; app invocation logs add execution context.
AWS AgentCore Browser: Live View allows real-time browser interaction. Custom browsers support recording to your S3 bucket, with replay through the AWS Console. CloudWatch and CloudTrail provide additional operational visibility.
Compare deployment ownership
Kernel: Kernel Apps move the automation process next to the browser. Alternatively, an external process can control a browser through the browser API. Choose based on execution locality and deployment ownership.
AWS AgentCore Browser: Use an AWS-managed Browser Tool or configure a custom browser with recording, networking and an execution role. Keep the controller's deployment separate in the architecture and operational estimate.
How to evaluate this choice
For short tools, lifecycle overhead can dominate. For a browser that stays open, action latency, task completion and drift matter more. Select the measurement that resembles your application.
- Use the same target page, browser configuration and controller workload.
- Record the runner and browser regions, account plan and concurrency.
- Keep the measured sample count and any warmup or retry behavior visible.
- Calculate tail percentiles from per-session totals, not sums of phase percentiles.
- Classify configuration failures before interpreting them as product failures.
Published browser measurements
These are the latest provider runs in the saved BrowserArena snapshot checked on October 18, 2026. Dates and runner environments can differ. A lifecycle test opens, connects, navigates and releases a browser; the throughput test runs a separate browser action sequence. Neither measures managed authentication or deployed Function reliability.
Use these observations to choose what to test in your application. An account-configuration failure, an incompatible page action and a timed-out navigation require different interpretations. BrowserArena is maintained by Notte and publishes its source and methodology.
| Provider | Lifecycle median | Lifecycle P95 | Actions / second | Run dates |
|---|---|---|---|---|
| Kernel | 334 ms | 700 ms | 3.32 | 2026-10-18 / 2026-10-17 |
| AWS AgentCore Browser | 2791 ms | 3472 ms | 0.72 | 2026-10-18 / 2026-10-17 |
Sources: browserarena.ai [1] ↗browserarena.ai [2] ↗github.com [3] ↗
Which approach fits?
Choose Kernel when your code makes many browser calls and you want to deploy it beside the browser, or you need Kernel's managed sign-in flow.
Kernel tradeoff: Browser-local code changes the deployment model. Check app action behavior, account limits and persistent-state ownership before moving an external worker into it.
Choose AWS AgentCore Browser when your application already uses AWS identity, logging and storage, and browser workflows need to fit those systems.
AWS AgentCore Browser tradeoff: The browser tool is not the entire AgentCore platform. Do not assign capabilities from unrelated AgentCore execution or identity products to a browser session without specifying the composition.
A useful acceptance check
Write a pass/fail result for the real task before running the evaluation. Record the account, configuration and code version next to that result. Repeat failures need an explanation, not an automatically different browser configuration.
When Notte belongs on this shortlist
Kernel's browser-local Apps make execution placement part of the decision. Compare the repeated action path with the proposed Notte controller or Function deployment before concluding that a lifecycle or hourly-rate difference decides the workflow.
AgentCore Browser's AWS integration can matter more than moving a browser endpoint. Retain AWS identity and observability requirements in the evaluation, and separately account for the code runner and website login before comparing Notte's integrated workflow.
Notte: Create an owned browser session, connect Playwright or Puppeteer over CDP, and stop the session when the work finishes. Browser lifecycle management remains necessary even when the control socket disconnects.
Consider this third option when its documented mechanism addresses a requirement left open by the two providers above. A working configuration on either original provider can still be the better choice; compare the task and ownership cost before switching.
Sources: kernel.sh [1] ↗docs.aws.amazon.com [2] ↗docs.notte.cc [3] ↗