Is Cosign or Kong better?

Neither clearly leads. Cosign starts at Free and Kong at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.

Which is cheaper, Cosign or Kong?

Cosign starts at Free and Kong at Free.

Does Cosign or Kong run on more platforms?

Cosign runs on macOS, Linux, Windows, Docker. Kong runs on Linux, Docker, Kubernetes.

Can I use Cosign for free?

Both have a free tier, so you can try either at no cost before committing.

What is Cosign best used for?

Cosign is most often used for signing container images in a build pipeline without managing long-lived private keys, attaching a signed bill of materials to a release so consumers can verify its provenance, meeting a customer or regulatory requirement for signed artifacts, verifying third-party images before they enter an internal registry. Of those, signing container images in a build pipeline without managing long-lived private keys and attaching a signed bill of materials to a release so consumers can verify its provenance are not what Kong is typically brought in for.

What can Cosign do that Kong cannot?

Cosign covers Keyless signing, Key and KMS signing, Registry-native storage, In-toto attestations. Kong covers API Gateway, Authentication & Authorization, Rate Limiting, Kubernetes.

Cybersecurity · head to head

Cosign vs Kong

Cosign

Cybersecurity

Signs and verifies container images and artifacts, with or without managing keys

From: Free
Rated: -

Full review Website

Kong

APIs

Cloud-native API gateway and service connectivity platform

From: Free
Rated: -

Full review Website

The short version

Each has a real cost: Cosign keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.; Kong the Plus plan includes 1M API requests a month and charges $200 a month for each additional million
They diverge on capability: Cosign covers Keyless signing, Kong covers API Gateway.
Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Cosign and Kong actually diverge.

Attributes where Cosign and Kong differ
Attribute	Cosign	Kong
Pricing model	Open source, no licence fee	subscription
Platforms	macOS, Linux, Windows, Docker	Linux, Docker, Kubernetes
Category	Cybersecurity	APIs
Founded	Unknown	2010

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 Cosign

Keyless signing
Key and KMS signing
Registry-native storage
In-toto attestations
Offline verification
Trusted root and signing config

Only in Kong

API Gateway
Authentication & Authorization
Rate Limiting
Kubernetes
Consul
Eureka
PostgreSQL
Linux support

What people use each for

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

Cosign

Signing container images in a build pipeline without managing long-lived private keysnot Kong
Attaching a signed bill of materials to a release so consumers can verify its provenancenot Kong
Meeting a customer or regulatory requirement for signed artifactsnot Kong
Verifying third-party images before they enter an internal registrynot Kong

Kong

API gateway management and routingnot Cosign
API development and testingnot Cosign
Enterprise API security and governancenot Cosign

Where each one falls short

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

Cosign

Keyless signing inherits every weakness of the identity provider behind it. Sigstore’s own threat model states that if an identity provider is compromised, Sigstore will issue certificates to those identities, so a compromised account produces perfectly valid signatures.
A signature proves who signed, never whether they should have. The documentation is explicit that Sigstore cannot determine authorisation, so every consumer must write and maintain their own identity and issuer policy or verification means nothing.
Nothing is enforced without an admission controller. Signing changes what you can prove, not what runs, and the official policy controller has a small maintainer base for a component sitting in a cluster admission path.
Upgrades break pipelines. Version 3 changed defaults, version 4 is announced as removing legacy functionality and roughly half the command line flags, and two official client libraries still lacked support for the new log format as of mid 2026.
Signatures do not expire. An artifact signed before a maintainer account was compromised and one signed after are indistinguishable unless somebody is actively monitoring the transparency log, and almost nobody is.

Kong

The Plus plan includes 1M API requests a month and charges $200 a month for each additional million
Plus is capped at 10M requests a month, so growth past that forces an Enterprise contract
Plus limits published APIs to 20 and includes one Developer Portal, with a second at $200 a month
SSO and audit logging are Enterprise only
Enterprise pricing is custom and billed annually

Pricing, plan by plan

Cosign

Free

CosignFree
- Apache-2.0
- Public Sigstore infrastructure free to use
- No usage limits published

Kong

Free

Kong Konnect Free TrialFree
- 30-day free trial
- Full enterprise functionality
- Unlimited gateways
Kong Konnect Plus$null/month
- Per gateway pricing billed monthly
- Up to 5 Serverless Gateways, 2 Hybrid, 2 Dedicated Cloud Gateways
- 1M API requests included per month
Kong Insomnia EssentialsFree
- Unlimited projects and CLI access
- Up to 3 Git Sync users
- 1,000 mock server requests per month
Kong Insomnia Pro$12/month
- Unlimited users with Git Sync access
- Unlimited organizations
- RBAC

Which should you pick?

Choose Cosign if

You need keyless signing.
You want to start without paying.
You work on macOS, Linux, Windows, Docker.
You also want key and kms signing.

Cosign review

Choose Kong if

You need api gateway.
You want to start without paying.
You work on Linux, Docker, Kubernetes.
You also want authentication & authorization.

Kong review

Questions people ask

Is Cosign or Kong better?: Neither clearly leads. Cosign starts at Free and Kong at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Cosign or Kong?: Cosign starts at Free and Kong at Free.
Does Cosign or Kong run on more platforms?: Cosign runs on macOS, Linux, Windows, Docker. Kong runs on Linux, Docker, Kubernetes.
Can I use Cosign for free?: Both have a free tier, so you can try either at no cost before committing.
What is Cosign best used for?: Cosign is most often used for signing container images in a build pipeline without managing long-lived private keys, attaching a signed bill of materials to a release so consumers can verify its provenance, meeting a customer or regulatory requirement for signed artifacts, verifying third-party images before they enter an internal registry. Of those, signing container images in a build pipeline without managing long-lived private keys and attaching a signed bill of materials to a release so consumers can verify its provenance are not what Kong is typically brought in for.
What can Cosign do that Kong cannot?: Cosign covers Keyless signing, Key and KMS signing, Registry-native storage, In-toto attestations. Kong covers API Gateway, Authentication & Authorization, Rate Limiting, Kubernetes.

Answered from the vendors’ own pages

Cosign: Does Cosign tell me if an image is vulnerable?

No. It has no vulnerability knowledge whatsoever. It can carry an SBOM as a signed attestation but never reads it. Pair it with a scanner.

Kong: Does Kong offer a free trial?

Yes, Kong Konnect offers a 30-day free trial with full enterprise functionality, unlimited gateways, and no credit card required.

Source

Cosign: Is signing alone enough?

No. Verification is a command somebody runs. Without an admission controller enforcing it, an unsigned image still runs.

Kong: How much does Kong Insomnia Pro cost?

Kong Insomnia Pro is $12 per user per month with 15% savings available for annual billing.

Source

Cosign: What does a bare cosign verify actually prove?

Very little. Without a pinned certificate identity and OIDC issuer, it accepts a valid signature from any identity at all.

Kong: What are Kong Konnect Plus API request limits?

Kong Konnect Plus includes 1M API requests per month; additional requests cost $200 per 1M (maximum 10M per month).

Source

Cosign: What is the risk of keyless signing?

Your OIDC provider becomes the root of trust. Compromise of that account yields genuine, verifiable signatures, so account security is the control that matters.

Kong: What is included in Kong Insomnia Enterprise?

Kong Insomnia Enterprise is $45 per user per month with SSO, SCIM, vault integrations, unlimited mock server requests, and Konnect integration.

Source

Cosign: Should we expect breaking changes?

Yes. Version 4 is announced to remove roughly half the flags, and a post-quantum migration is named as a further breaking change after that.

Cosign vs Kong

Cosign

Kong

The short version

Where they differ

What each one covers

Only in Cosign

Only in Kong

What people use each for

Cosign

Kong

Where each one falls short

Cosign

Kong

Pricing, plan by plan

Cosign

Kong

Which should you pick?

Choose Cosign if

Choose Kong if

Questions people ask

Answered from the vendors’ own pages

Related pages

More on Cosign

More on Kong

Keep looking

Other head to heads