Softwr

Testing · head to head

k6 vs Kong Gateway

k6 logo

k6

Testing

Load testing tool with JavaScript tests on a Go runtime, now owned by Grafana Labs

From
Free
Rated
-
Full reviewWebsite
Kong Gateway logo

Kong Gateway

APIs

Open-source and cloud API gateway for managing microservices traffic

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: k6 tests run on a JavaScript engine embedded in Go rather than on Node.js, so npm packages, Node built-ins and existing shared test utilities generally do not work without being bundled to plain JavaScript, and often not even then.; Kong Gateway the free open-source gateway lacks the analytics, portals, and support of the paid Konnect tiers.
  • They diverge on capability: k6 covers JavaScript test scripts, Kong Gateway covers API request routing.
  • Prices and features above were last checked on 30 August 2026.

Where they differ

Only the attributes on which k6 and Kong Gateway actually diverge.

Attributes where k6 and Kong Gateway differ
Attributek6Kong Gateway
Pricing modelOpen source, no licence feefreemium
PlatformsWindows, macOS, Linux, Docker, Kubernetesweb, linux, api
CategoryTestingAPIs
FoundedUnknown2017

Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated).

What each one covers

Drawn from each product's published feature list. An absence here means we hold no record of it - not that the product lacks it.

Only in k6

  • JavaScript test scripts
  • Thresholds and checks
  • Protocol coverage
  • Browser module
  • Executors
  • xk6 extensions
  • Metrics output
  • Kubernetes operator

Only in Kong Gateway

  • API request routing
  • Plugin ecosystem
  • Developer portals
  • AI Gateway
  • Analytics and observability
  • SSO and audit logs

What people use each for

The jobs each tool is most often brought in to do.

k6

  • Gating a deployment pipeline on a threshold such as 95th percentile latency under a defined arrival ratenot Kong Gateway
  • Generating tens of thousands of requests per second from a small number of machines without a load generator fleetnot Kong Gateway
  • Testing gRPC and WebSocket services with the same tooling and thresholds used for HTTP endpointsnot Kong Gateway
  • Correlating a load test against existing dashboards for an organisation already running Grafana and Prometheusnot Kong Gateway

Kong Gateway

  • Routing and securing traffic across microservicesnot k6
  • Publishing internal or external developer portalsnot k6
  • Managing rate limits and authentication at the API edgenot k6
  • Gateway-level routing to multiple LLM providersnot k6

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

k6

  • Tests run on a JavaScript engine embedded in Go rather than on Node.js, so npm packages, Node built-ins and existing shared test utilities generally do not work without being bundled to plain JavaScript, and often not even then.
  • The open source binary runs on a single machine, so distributed load requires the Kubernetes operator or the cloud service, and the operator is infrastructure your team has to run and debug.
  • The AGPL-3.0 licence on the core requires legal review at any company that intends to embed k6 in a product it distributes or offers as a service, which is a slower path than a permissively licensed tool.
  • There is no result storage in the open source tool, so trend history means standing up Prometheus, InfluxDB or Grafana Cloud before load testing produces anything comparable over time.
  • Since the Grafana Labs acquisition the roadmap serves the Grafana observability stack, so a buyer choosing k6 as a standalone tool should expect the standalone experience to receive less investment than the cloud and dashboard integration.
  • Grafana Cloud billing is by virtual user hour, so a long soak test at modest concurrency costs far more than its peak load suggests, and cost planning has to be done in virtual user hours rather than in test runs.

Kong Gateway

  • The free open-source gateway lacks the analytics, portals, and support of the paid Konnect tiers.
  • Plus tier caps API requests at 1M/month before incurring per-million overage charges.
  • Enterprise pricing is custom and not published, making budgeting harder without sales contact.
  • Configuration and plugin management can require significant operational expertise to run at scale.

Pricing, plan by plan

k6

Free
  • k6 OSSFree
    • AGPL-3.0 licence
    • Full test engine, no virtual user limits
    • Runs on one machine unless distributed yourself
  • Grafana Cloud free tierFree
    • Includes a monthly allowance of virtual user hours
    • Hosted test results and dashboards
    • Shared with the rest of the Grafana Cloud free tier
  • Grafana Cloud k6$undefined/month
    • Billed by virtual user hours consumed
    • Load generation from multiple regions
    • Retained test history and comparison

Kong Gateway

Free
  • Free TrialFree
    • 30-day enterprise functionality trial
    • Unlimited gateways
    • 30-day analytics retention
  • Plus$undefined/month
    • Up to 5 serverless, 2 hybrid, 2 dedicated cloud gateways
    • 1M API requests/month included
    • Up to 2 developer portals
  • Enterprise$undefined/month
    • Unlimited hybrid and dedicated cloud gateways
    • Unlimited developer portals
    • SSO and audit logs

Which should you pick?

Choose k6 if

  • You need javascript test scripts.
  • You want to start without paying.
  • You work on Windows, macOS, Linux, Docker, Kubernetes.
  • You also want thresholds and checks.
k6 review

Choose Kong Gateway if

  • You need api request routing.
  • You want to start without paying.
  • You work on web, linux, api.
  • You also want plugin ecosystem.
Kong Gateway review

Questions people ask

Is k6 or Kong Gateway better?
Neither clearly leads. k6 starts at Free and Kong Gateway at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, k6 or Kong Gateway?
k6 starts at Free and Kong Gateway at Free.
Does k6 or Kong Gateway run on more platforms?
k6 runs on Windows, macOS, Linux, Docker, Kubernetes. Kong Gateway runs on web, linux, api.
Can I use k6 for free?
Both have a free tier, so you can try either at no cost before committing.
What is k6 best used for?
k6 is most often used for gating a deployment pipeline on a threshold such as 95th percentile latency under a defined arrival rate, generating tens of thousands of requests per second from a small number of machines without a load generator fleet, testing grpc and websocket services with the same tooling and thresholds used for http endpoints, correlating a load test against existing dashboards for an organisation already running grafana and prometheus. Of those, gating a deployment pipeline on a threshold such as 95th percentile latency under a defined arrival rate and generating tens of thousands of requests per second from a small number of machines without a load generator fleet are not what Kong Gateway is typically brought in for.
What can k6 do that Kong Gateway cannot?
k6 covers JavaScript test scripts, Thresholds and checks, Protocol coverage, Browser module. Kong Gateway covers API request routing, Plugin ecosystem, Developer portals, AI Gateway.

Answered from the vendors’ own pages

k6: Can I use npm packages in a k6 test?

Usually not. Scripts run on a Go-embedded JavaScript engine with no Node.js runtime, so packages depending on Node built-ins fail and pure JavaScript libraries must be bundled first.

Kong Gateway: Is Kong Gateway free?

Kong's core gateway is open source and free to self-host. Kong Konnect, the managed cloud platform, offers a 30-day free trial before moving to paid Plus or custom Enterprise pricing.

Source
k6: Is k6 free?

The core tool is free under AGPL-3.0 with no virtual user limits. Grafana Cloud k6 is a paid service billed by virtual user hours, with a free monthly allowance.

Kong Gateway: How is usage metered on the Plus plan?

The Plus plan includes 1M API requests per month, with additional usage billed at $200 per extra 1 million requests up to a 10M/month cap, plus per-gateway and per-LLM-model charges.

Source
k6: Does the Grafana acquisition affect the open source tool?

The tool remains open source and maintained, but investment is directed at making it a data source for Grafana, so standalone use is supported rather than prioritised.

Kong Gateway: What support is included?

Plus includes email support with a 2-business-day SLA, while Enterprise adds dedicated success managers and professional services.

Source
k6: Can k6 replace a browser testing tool?

No. The browser module measures page-level metrics under load, but functional browser testing belongs in Playwright or a similar tool.

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