M3
M3 is an open-source metrics engine for teams scaling Prometheus-based monitoring and centralizing metrics storage.
What M3 is
M3 is an open-source metrics engine for teams scaling Prometheus-based monitoring and centralizing metrics storage. Its M3DB component stores real-time metrics in a distributed time-series database designed for long retention. It supports PromQL, Graphite, and M3QL queries, and accepts data through Prometheus remote write, StatsD, Carbon plaintext, InfluxDB line protocol, and JSON. The project describes integrations with Prometheus, Graphite, Grafana, and InfluxDB, plus horizontal scaling. It can be installed with binaries or Docker, and the documentation covers Kubernetes cluster deployment. M3 describes a replication model with three copies and quorum reads and writes, and reports an 11X compression ratio. It is available under the Apache 2 license, with contributions welcomed and community support through Slack and GitHub. The project began at Uber’s Observability team in 2014. M3 is free: the listed open-source plan is free. M3DB is not a general-purpose time-series database; large-scale backfilling is not currently possible, and stored values are optimized for float64.
Good
- Free, open-source Apache 2 project
- Supports PromQL, Graphite, and M3QL
- Accepts five listed ingestion methods
- Supports horizontal scaling and retention policies
- Deployable with binaries, Docker, or Kubernetes
Watch out
- Not intended as a general-purpose time-series database
- Large-scale backfilling is not currently possible
- Stored values are optimized for float64
Who it suits
M3 suits teams building Prometheus-based monitoring that need centralized, long-retention metrics storage and horizontal scaling. It is also relevant to developers who want an open-source tool with PromQL and Graphite query support.
Verdict
M3 brings a broad set of ingestion options and query compatibility to Prometheus-centered metrics storage. Its stated limits around backfilling and general-purpose use are important to consider before adopting it.
Plans and prices
From M3's own pricing page, checked 11 Oct 2026.
| Plan | Price | What it gives you |
|---|---|---|
| M3 (open source) | Free | Open-source metrics engine; no commercial plan or usage limits stated |
The facts
Each one read from M3's own pages, with the date it was checked.
What it does
- Compression
- The home page reports an optimized compression algorithm with an 11X compression ratio.checked 11 Oct 2026
- Deployment
- M3 can be installed with binaries or Docker, and its documentation includes cluster deployment with Kubernetes.checked 11 Oct 2026
- Ingestion formats
- M3 supports Prometheus, StatsD, and Carbon ingestion formats.checked 11 Oct 2026
- Integrations
- The documentation describes integrations with Prometheus, Graphite, Grafana, and InfluxDB.checked 11 Oct 2026
- Limitations
- M3DB is not intended as a general-purpose time-series database; large-scale backfilling is not currently possible and stored values are optimized for float64.checked 11 Oct 2026
- Open source
- M3 is open-sourced under the Apache 2 license, and contributions are welcomed.checked 11 Oct 2026
- Origin
- M3 began as an open-source metrics platform developed by Uber’s Observability team in 2014.checked 11 Oct 2026
- Purpose
- M3 is a Prometheus-compatible metrics engine for scaling Prometheus-based monitoring and centralized metrics storage.checked 11 Oct 2026
- Query compatibility
- M3 advertises 100% PromQL compatibility and supports Graphite query languages.checked 11 Oct 2026
- Reliability
- The home page describes three data replicas with quorum writes and reads for consistency.checked 11 Oct 2026
- Scale
- The home page says M3 has been used to store tens of billions of active metric time series.checked 11 Oct 2026
- Storage
- M3DB is a distributed time-series database for storing real-time metrics at long retention.checked 11 Oct 2026
- Support
- The project links to a community Slack and GitHub repository.checked 11 Oct 2026
Alternatives to M3
- 1
TDengine
Free planOpen sourceWebAPILinuxmacOS8.3Free plan - 2
Amazon Timestream
Free planWebAPILinuxmacOS7.9Free plan - 3
Apache IoTDB
Free planOpen sourceWebAPILinuxmacOS7.7Free plan - 4
InfluxDB
Free planWebAPILinuxmacOS7.4$0.01 usage-based - 5
VictoriaMetrics
Free planWebAPILinuxmacOS7.4From $200 a month - 6
LinDB
Free planWebAPILinuxmacOS6.9Free plan