Network & Connectivity · head to head
Splunk vs Prometheus
Prometheus
Network & Connectivity
Open source monitoring and alerting toolkit for cloud native environments
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Splunk no prices are published on any plan; every model requires contacting sales for an estimate; Prometheus not suitable for per-request billing as collected data lacks 100% accuracy
- They diverge on capability: Splunk covers Log aggregation, Prometheus covers Multi-dimensional Data Model.
Where they differ
Only the attributes on which Splunk and Prometheus actually diverge.
| Attribute | Splunk | Prometheus |
|---|---|---|
| Pricing model | usage-based | open-source |
| Platforms | Web, Api | Linux, macOS, Windows |
| Founded | 2003 | 2015 |
Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Network & Connectivity).
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 Splunk
- Log aggregation
- Real-time monitoring
- Data visualization
- Full-text search
- Custom dashboards
- Alert management
- Anomaly detection
- Log parsing
Only in Prometheus
- Multi-dimensional Data Model
- PromQL Query Language
- Pull-based Collection
- Service Discovery
- Alerting Rules
- Federation
- Local Storage
- Grafana
What people use each for
The jobs each tool is most often brought in to do.
Splunk
- Log search and analysis across infrastructurenot Prometheus
- SIEM, SOAR and UEBA for a security operations teamnot Prometheus
- Application performance and infrastructure monitoringnot Prometheus
- Cloud, private cloud or on-premises deploymentnot Prometheus
Prometheus
- Cloud-native monitoring and alertingnot Splunk
- Time-series metrics collectionnot Splunk
- Infrastructure monitoringnot Splunk
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Splunk
- No prices are published on any plan; every model requires contacting sales for an estimate
- Three separate pricing models, workload, ingest and entity, so the same deployment costs different amounts depending on which was signed
- Ingest pricing bills on data volume, so cost tracks how much you log rather than how much value you get from it
- Security, observability and platform are priced separately
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
Pricing, plan by plan
Splunk
Free- FreeFree
- Log aggregation
- Real-time monitoring
- Data visualization
Prometheus
FreeNo published plan breakdown. See the Prometheus review.
Which should you pick?
Choose Splunk if
- You need log aggregation.
- You want to start without paying.
- You work on Web, Api.
- You also want real-time monitoring.
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.
Questions people ask
- Is Splunk or Prometheus better?
- Neither clearly leads. Splunk starts at Free and Prometheus at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Splunk or Prometheus?
- Splunk starts at Free and Prometheus at Free.
- Does Splunk or Prometheus run on more platforms?
- Splunk runs on Web, Api. Prometheus runs on Linux, macOS, Windows.
- Can I use Splunk for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Splunk best used for?
- Splunk is most often used for log search and analysis across infrastructure, siem, soar and ueba for a security operations team, application performance and infrastructure monitoring, cloud, private cloud or on-premises deployment. Of those, log search and analysis across infrastructure and siem, soar and ueba for a security operations team are not what Prometheus is typically brought in for.
- What can Splunk do that Prometheus cannot?
- Splunk covers Log aggregation, Real-time monitoring, Data visualization, Full-text search. Prometheus covers Multi-dimensional Data Model, PromQL Query Language, Pull-based Collection, Service Discovery.