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Cybersecurity · head to head

Microsoft Defender vs Sigstore

Microsoft Defender logo

Microsoft Defender

Cybersecurity

Always-on protection for you and your family's data and devices

From
$12/month
Rated
-
Full reviewWebsite
Sigstore logo

Sigstore

Cybersecurity

Free public signing and transparency infrastructure for open source artifacts

From
Free
Rated
-
Full reviewWebsite

The short version

  • Only Sigstore has a free tier, so it costs nothing to try first.
  • Each has a real cost: Microsoft Defender defender Suite requires existing Microsoft 365 E3 or equivalent base licensing; Sigstore the security model depends on somebody watching the log. The documentation states that compromise of an identity provider or of Fulcio itself is detectable only if third parties monitor the transparency log, the monitoring tool is a community-tier rather than core project, and almost no consumer runs one.
  • Prices and features above were last checked on 31 August 2026.

Where they differ

Only the attributes on which Microsoft Defender and Sigstore actually diverge.

Attributes where Microsoft Defender and Sigstore differ
AttributeMicrosoft DefenderSigstore
Starting price$12/monthFree
Pricing modelsubscriptionOpen source, public instance free to use
Free tierNoYes
PlatformsWebWeb, Linux, macOS, Windows, Self-hosted

Identical on both: user rating (Not yet rated), category (Cybersecurity).

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 Microsoft Defender

Nothing recorded that Sigstore does not also cover.

Only in Sigstore

  • Fulcio
  • Rekor
  • Keyless signing
  • Multi-language clients
  • Timestamp authority
  • Neutral governance

What people use each for

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

Microsoft Defender

  • Endpoint security and threat protectionnot Sigstore
  • Identity and access securitynot Sigstore
  • Email threat protectionnot Sigstore
  • SaaS application security monitoringnot Sigstore

Sigstore

  • Open source projects signing releases without running a certificate authoritynot Microsoft Defender
  • Organisations meeting a signed-artifact requirement without buying a signing productnot Microsoft Defender
  • Publishing provenance that a consumer can verify independently of younot Microsoft Defender
  • Self-hosting the same components where a public log is unacceptablenot Microsoft Defender

Where each one falls short

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

Microsoft Defender

  • Defender Suite requires existing Microsoft 365 E3 or equivalent base licensing
  • Some Defender products use pay-as-you-go pricing with variable costs
  • Prices vary based on Microsoft agreements, requiring sales contact for custom quotes

Sigstore

  • The security model depends on somebody watching the log. The documentation states that compromise of an identity provider or of Fulcio itself is detectable only if third parties monitor the transparency log, the monitoring tool is a community-tier rather than core project, and almost no consumer runs one.
  • It is a 99.5 percent objective with no service level agreement, which permits several hours of downtime a month and offers no remedy. A pipeline that signs on every build has taken a hard dependency on a free service with no contract behind it.
  • Log scale is a live engineering problem rather than a theoretical one. The active shard holds billions of entries, the log has already been sharded twice, and sharding version 1 requires stopping traffic, which is why a replacement was built.
  • Ten-minute certificates make trust depend on log availability. Verifying an older signature relies on the log entry proving it was made inside that window, so a lost or unreachable entry can render a valid artifact unverifiable.
  • Migration debt is substantial and ongoing. Version 2 of the log is generally available but not the public default, the signing client has an announced breaking release ahead, some official clients lag the new log format, and a post-quantum migration is named as the next break after that.

Pricing, plan by plan

Microsoft Defender

$12/month
  • Microsoft Defender Suite$12/month
    • Endpoint protection
    • Identity threat detection
    • Email security
  • Microsoft 365 E5 with Defender$60/month
    • Includes Defender Suite
    • Microsoft Teams included
    • Comprehensive security and compliance
  • Microsoft Defender Vulnerability Management Add-on$2/month
    • Vulnerability scanning and management
    • One-month free trial available
    • Annual commitment required

Sigstore

Free
  • Public good instanceFree
    • Free to everyone with no contract
    • 99.5 percent availability objective, not an agreement
    • 100KB cap per attestation upload
  • Self-hostedFree
    • Apache-2.0
    • Run your own Fulcio and Rekor
    • Rekor v2 available for self-hosters

Which should you pick?

Choose Microsoft Defender if

Nothing in the data separates Microsoft Defender from Sigstore on the points above - pick on price and on how each one feels to use.

Microsoft Defender review

Choose Sigstore if

  • You need fulcio.
  • You want to start without paying.
  • You work on Web, Linux, macOS, Windows, Self-hosted.
  • You also want rekor.
Sigstore review

Questions people ask

Is Microsoft Defender or Sigstore better?
Neither clearly leads. Microsoft Defender starts at $12/month and Sigstore at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Microsoft Defender or Sigstore?
Sigstore has a free tier; the other does not. Paid plans start at $12/month for Microsoft Defender and Free for Sigstore.
Does Microsoft Defender or Sigstore run on more platforms?
Microsoft Defender runs on Web. Sigstore runs on Web, Linux, macOS, Windows, Self-hosted.
Can I use Sigstore for free?
Yes. Sigstore has a free tier, so you can try it without paying. Microsoft Defender starts at $12/month.
What is Microsoft Defender best used for?
Microsoft Defender is most often used for endpoint security and threat protection, identity and access security, email threat protection, saas application security monitoring. Of those, endpoint security and threat protection and identity and access security are not what Sigstore is typically brought in for.
What can Microsoft Defender do that Sigstore cannot?
Sigstore covers Fulcio, Rekor, Keyless signing, Multi-language clients.

Answered from the vendors’ own pages

Microsoft Defender: How much does Microsoft Defender Suite cost?

Microsoft Defender Suite costs $12/user/month (paid yearly), but requires existing Microsoft 365 E3 or equivalent base licensing. It includes endpoint protection, identity threat detection, email security, and SaaS application monitoring.

Source
Sigstore: Is the public instance really free?

Yes, with no contract and no paid tier. That is also the weakness: a 99.5 percent objective with no agreement, no remedy and support through Slack.

Microsoft Defender: What add-ons are available for Microsoft Defender?

Microsoft Defender Vulnerability Management Add-on costs $2/user/month with annual commitment and includes a one-month free trial. Additional pay-as-you-go products include External Attack Surface Management, Cloud Security Posture Management, and Sentinel.

Source
Sigstore: Has the public log moved to Rekor v2?

No. Version 2 reached general availability in October 2025 and self-hosters can use it, but the public instance still defaults to version 1 and the project has said it will for the foreseeable future.

Microsoft Defender: Is Defender included in Microsoft 365 E5?

Yes, Microsoft Defender Suite is included in Microsoft 365 E5 at $60/user/month (paid yearly with Teams). Prices may vary based on Microsoft agreements, requiring contact with Sales for customized quotes.

Source
Sigstore: Does Sigstore make my dependencies safe?

No, and this is a category error worth avoiding. It tells you who published something. It has no knowledge of what the artifact contains or whether it is vulnerable.

Sigstore: What are the rate limits?

Not published. Only the 100KB cap per attestation upload is documented, so do not design a high-volume pipeline around assumed throughput.

Sigstore: Should we self-host it?

If a public record of every signature is unacceptable, or if a free service with no agreement cannot sit in your build path, then yes. Otherwise the public instance is what most projects use.

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