Softwr

Networking · head to head

Prometheus vs Vault

Prometheus logo

Prometheus

Networking

Open source monitoring and alerting toolkit for cloud native environments

From
Free
Rated
-
Full reviewWebsite
Vault logo

Vault

Cloud

Manage Secrets and Protect Sensitive Data

From
Free
Rated
-
Full reviewWebsite

The short version

  • Each has a real cost: Prometheus not suitable for per-request billing as collected data lacks 100% accuracy; Vault vault 1.15.0 and later is licensed under the Business Source License 1.1, not an OSI open source licence, with IBM Corporation as licensor
  • They diverge on capability: Prometheus covers Multi-dimensional Data Model, Vault covers Secrets management.

Where they differ

Only the attributes on which Prometheus and Vault actually diverge.

Attributes where Prometheus and Vault differ
AttributePrometheusVault
PlatformsLinux, macOS, WindowsLinux, Windows, Mac, Cloud
CategoryNetworkingCloud

Identical on both: starting price (Free), pricing model (open-source), free tier (Yes), user rating (Not yet rated), founded (2015).

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 Prometheus

  • Multi-dimensional Data Model
  • PromQL Query Language
  • Pull-based Collection
  • Service Discovery
  • Alerting Rules
  • Federation
  • Local Storage
  • Grafana

Only in Vault

  • Secrets management
  • Encryption
  • Authentication
  • Authorization
  • Audit logging
  • API access
  • High availability
  • Replication

Both cover

  • Kubernetes

What people use each for

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

Prometheus

  • Monitoring and alerting systemnot Vault
  • Time-series databasenot Vault
  • Infrastructure metrics collectionnot Vault

Vault

  • Centrally storing and rotating secrets, API keys and database credentialsnot Prometheus
  • Issuing short-lived dynamic credentials to applications instead of static passwordsnot Prometheus
  • Encryption as a service and PKI certificate issuancenot Prometheus

Where each one falls short

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

Prometheus

  • Not suitable for per-request billing as collected data lacks 100% accuracy
  • Hard limit on scrape body size; large responses cause scrape failure
  • Per-scrape sample limit enforced; exceeding limit marks targets as failed
  • Not designed for long-term durable storage; optimised for metrics collection

Vault

  • Vault 1.15.0 and later is licensed under the Business Source License 1.1, not an OSI open source licence, with IBM Corporation as licensor
  • The Additional Use Grant forbids offering Vault to third parties on a hosted or embedded basis in a paid product that competes with IBM's paid versions of Vault
  • Each version only converts to MPL 2.0 four years after that version is published, and the Change Date is tracked per version
  • Replication, HSM support, namespaces, performance standby nodes, FIPS builds, control group authorisation, multi-factor authentication, secrets sync and lease count quotas all require a Vault Enterprise licence
  • A Vault Enterprise licence must be applied to the cluster before any Enterprise feature can be used

Pricing, plan by plan

Prometheus

Free
  • Prometheus (Open Source)Free
    • 100% open source
    • Community-driven project
    • Apache 2 License

Vault

Free
  • Open SourceFree
    • Secrets management
    • Encryption as a service
    • Identity management
  • EnterpriseFree
    • Advanced features
    • Premium support
    • Dedicated updates

Which should you pick?

Choose Prometheus if

  • You need multi-dimensional data model.
  • You want to start without paying.
  • You work on Linux, macOS, Windows.
  • You also want promql query language.
Prometheus review

Choose Vault if

  • You need secrets management.
  • You want to start without paying.
  • You work on Linux, Windows, Mac, Cloud.
  • You also want encryption.
Vault review

Questions people ask

Is Prometheus or Vault better?
Neither clearly leads. Prometheus starts at Free and Vault at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Prometheus or Vault?
Prometheus starts at Free and Vault at Free.
Does Prometheus or Vault run on more platforms?
Prometheus runs on Linux, macOS, Windows. Vault runs on Linux, Windows, Mac, Cloud.
Can I use Prometheus for free?
Both have a free tier, so you can try either at no cost before committing.
What is Prometheus best used for?
Prometheus is most often used for monitoring and alerting system, time-series database, infrastructure metrics collection. Of those, monitoring and alerting system and time-series database are not what Vault is typically brought in for.
What can Prometheus do that Vault cannot?
Prometheus covers Multi-dimensional Data Model, PromQL Query Language, Pull-based Collection, Service Discovery. Vault covers Secrets management, Encryption, Authentication, Authorization. Both handle Kubernetes.

Answered from the vendors’ own pages

Prometheus: What does Prometheus cost?

Prometheus is completely free and open source. There are no pricing tiers or paid plans. The entire project is licensed under Apache 2 and hosted on GitHub.

Source
Vault: Is HashiCorp Vault free to use?

Yes, Vault is available as a free, open-source project. The community version includes secrets management, certificate generation and rotation, encryption services, and credential management. Vault Enterprise is a commercial offering with additional features.

Source
Prometheus: Is Prometheus commercial software or free?

Prometheus is 100% open source and community-driven. It is a CNCF graduated project with no commercial restrictions or licensing fees.

Source
Vault: What are the differences between open-source Vault and Vault Enterprise?

Open-source Vault is free and self-hosted. Vault Enterprise includes additional features and commercial support. HashiCorp also offers Vault Dedicated on the HashiCorp Cloud Platform as a fully managed cloud option.

Source
Prometheus: How is Prometheus licensed?

Prometheus is licensed under the Apache 2 License, which permits free use, modification, and distribution for commercial and non-commercial purposes.

Source
Vault: Can I try HashiCorp Cloud Platform Vault without payment?

Yes, HashiCorp offers a free trial option for HCP Vault Dedicated. New users also receive a $500 credit to use across HashiCorp Cloud Platform services.

Source
Vault: What does Vault manage and protect?

Vault provides identity-based secrets management for users, machines, services, and AI agents. It automates authentication and authorization for access to secrets, passwords, certificates, encryption keys, and other sensitive data across your infrastructure.

Source
Share

Related pages

More on Prometheus

More on Vault

Keep looking

Other head to heads