Cloud · head to head
Azure Functions vs Thanos

Thanos
Cloud
Highly available Prometheus with long-term object storage
- From
- Free
- Rated
- -
The short version
- Each has a real cost: Azure Functions consumption plan free grant is capped at 1 million executions and 400,000 GB-seconds of resource consumption per month per subscription, billed per GB-second beyond that; Thanos several components — sidecar, store, querier, compactor, ruler — each with its own configuration and failure modes
Where they differ
Only the attributes on which Azure Functions and Thanos actually diverge.
| Attribute | Azure Functions | Thanos |
|---|---|---|
| Pricing model | usage-based | Open source, no licence fee |
| Platforms | Web | Kubernetes, Linux, Docker |
Identical on both: starting price (Free), free tier (Yes), user rating (Not yet rated), category (Cloud).
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 Azure Functions
Nothing recorded that Thanos does not also cover.
Only in Thanos
- Global query
- Object storage retention
- Deduplication
- Downsampling
What people use each for
The jobs each tool is most often brought in to do.
Azure Functions
- Event-driven computingnot Thanos
- Serverless application backendnot Thanos
- Scalable API endpointsnot Thanos
Thanos
- Querying metrics across many clusters or regions from one placenot Azure Functions
- Retaining metrics for years without local disk growthnot Azure Functions
- Removing the gap that appears when a single Prometheus instance restartsnot Azure Functions
Where each one falls short
Documented limitations, not opinions. Every one is a constraint you would hit in normal use.
Azure Functions
- Consumption plan free grant is capped at 1 million executions and 400,000 GB-seconds of resource consumption per month per subscription, billed per GB-second beyond that
- The newer Flex Consumption plan's free grant is smaller still, at 250,000 executions and 100,000 GB-seconds per month
- Premium plan avoids per-execution charges but bills continuously for allocated core seconds and memory regardless of invocation volume
- Memory is rounded up to the nearest 128 MB and execution time to the nearest 1 ms for billing, so small overages round upward
Thanos
- Several components — sidecar, store, querier, compactor, ruler — each with its own configuration and failure modes
- The compactor is a common source of operational trouble and must not run twice against the same bucket
- Query latency over object storage is meaningfully higher than local Prometheus
- Object storage costs and API request charges become real at high volume
Pricing, plan by plan
Azure Functions
Free- Consumption Plan$null/month
- 1 million requests free monthly
- 400,000 GB-seconds free monthly
- Billed per second and executions
- Flex Consumption Plan$null/month
- 250,000 executions free monthly
- 100,000 GB-seconds free monthly
- Event-driven scaling
- Premium Plan$null/month
- No execution charges
- At least one instance required
- Includes automatic scaling and VNET access
Thanos
Free- ThanosFree
- Full functionality
- No usage limits
- Community support
Which should you pick?
Choose Thanos if
- You need global query.
- You want to start without paying.
- You work on Kubernetes, Linux, Docker.
- You also want object storage retention.
Questions people ask
- Is Azure Functions or Thanos better?
- Neither clearly leads. Azure Functions starts at Free and Thanos at Free, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
- Which is cheaper, Azure Functions or Thanos?
- Azure Functions starts at Free and Thanos at Free.
- Does Azure Functions or Thanos run on more platforms?
- Azure Functions runs on Web. Thanos runs on Kubernetes, Linux, Docker.
- Can I use Azure Functions for free?
- Both have a free tier, so you can try either at no cost before committing.
- What is Azure Functions best used for?
- Azure Functions is most often used for event-driven computing, serverless application backend, scalable api endpoints. Of those, event-driven computing and serverless application backend are not what Thanos is typically brought in for.
- What can Azure Functions do that Thanos cannot?
- Thanos covers Global query, Object storage retention, Deduplication, Downsampling.
Answered from the vendors’ own pages
Azure Functions: Does Azure Functions have a free tier?
Yes, Azure Functions includes a monthly free grant of 1 million requests and 400,000 GB-seconds on the Consumption Plan, or 250,000 executions and 100,000 GB-seconds on Flex Consumption.
SourceThanos: Is Thanos free?
Yes, open source and CNCF-incubating. Costs are the object storage it uses.
Azure Functions: What is Azure Functions' pricing model?
Azure Functions uses usage-based pricing. Consumption plans charge per second of resource consumption and per execution, measured in gigabyte-seconds and rounded to the nearest 128 MB.
SourceThanos: Does Thanos replace Prometheus?
No. It runs alongside existing Prometheus servers, adding global query, deduplication and long-term storage.
Azure Functions: What is the minimum execution time for Azure Functions?
The minimum execution time is 100 milliseconds on Consumption plans. Premium plans charge based on core seconds and allocated memory.
SourceThanos: Thanos or VictoriaMetrics?
Thanos layers onto Prometheus using object storage and is the more established multi-cluster answer. VictoriaMetrics is a separate store aiming at lower resource use and fewer moving parts.
Related pages
More on Azure Functions
Other head to heads
- Azure Functions vs Grafana Cloud
- Azure Functions vs Neon
- Azure Functions vs DigitalOcean
- Azure Functions vs AWS (Amazon Web Services)
- Azure Functions vs Pulumi
- Azure Functions vs Fly.io
- Azure Functions vs Anyscale
- Azure Functions vs Fireworks AI
- Azure Functions vs Podman
- Azure Functions vs Railway
- Azure Functions vs Render
- Azure Functions vs Vault
- Azure Functions vs Wiz
- Azure Functions vs Beam Cloud
- Azure Functions vs Cerebrium
- Azure Functions vs DeepInfra
- Azure Functions vs Go
- Azure Functions vs Caddy
- Thanos vs Grafana Cloud
- Thanos vs Neon
- Thanos vs DigitalOcean
- Thanos vs AWS (Amazon Web Services)
- Thanos vs Pulumi
- Thanos vs Fly.io
- Thanos vs Anyscale
- Thanos vs Fireworks AI
- Thanos vs Podman
- Thanos vs Railway
- Thanos vs Render
- Thanos vs Vault
- Thanos vs Wiz
- Thanos vs Beam Cloud
- Thanos vs Cerebrium
- Thanos vs DeepInfra
- Thanos vs Go
- Thanos vs Caddy

