About ObservKit
ObservKit is an independent set of capacity planning calculators and guides for observability platforms — Splunk, Elasticsearch and vendor-neutral log storage — plus a few everyday DevOps utilities.
Why ObservKit exists
Observability storage is usually sized with spreadsheets and rules of thumb whose assumptions are not written down. Small modelling choices move the answer by tens of percent. In an illustrative RF3/SF2 example, treating Splunk index files as if they lived on every copy overstates an RF3/SF2 cluster by 30%; giving 60 days of Elasticsearch cold data a replica instead of mounting it as a searchable snapshot doubles cold-tier disk. ObservKit exists to make those choices explicit: every calculator shows its formula, its defaults and the documentation behind them, so the estimate can be checked rather than trusted.
That applies to ObservKit itself. Its first Splunk model used the 0.5 × RF shortcut; it was corrected in October 2026, and the change and its impact are recorded in the changelog.
What you will find
- Capacity planning calculators for generic log storage, Splunk (RF/SF and SmartStore) and Elasticsearch (data tiers, searchable snapshots, shards), with Expert mode, A/B scenario comparison, locally saved scenarios and printable reports.
- Guides that help choose the inputs: tier layouts, SmartStore cache sizing, retention planning.
- Methodology: the common model, sources, verification and changelog.
- DevOps utilities: cron, YAML / Kubernetes and Unix timestamp tools for the schedules, manifests and log timestamps that come with running these platforms.
How the content is maintained
Figures on reference pages and guides are generated by the same engines as the calculators and re-checked by automated tests. Pages carry a "Last reviewed" month that changes only when they are reviewed again. Content is published under the ObservKit name.
What ObservKit is not
It is not affiliated with or endorsed by Splunk, Elastic or the Cloud Native Computing Foundation, and its results are planning estimates, not official vendor sizing or a substitute for workload testing. There are no accounts and nothing to install.
Privacy-conscious by design
Calculator inputs are processed in your browser and are not sent to an ObservKit server. Saved scenarios stay in this browser's local storage. Details are in the privacy notice.
Contact
Found a formula or source that looks wrong? See how to get in touch.
ObservKit is an independent project and is not affiliated with, sponsored by or endorsed by Splunk LLC, Elasticsearch B.V. or The Linux Foundation. Splunk is a trademark or registered trademark of Splunk LLC in the United States and other countries. Elasticsearch is a trademark of Elasticsearch B.V., registered in the U.S. and in other countries. Kubernetes is a registered trademark of The Linux Foundation. Names are used only to identify the products the calculators model.