Log Message Size Calculator
Estimate log volume and storage from message rate and retention.
About Log Message Size Calculator
Log volume is the product of rate, size and retention, and compression at rest cuts it dramatically because logs are highly repetitive. Retention is usually the easiest lever to pull. Structured logging increases per-message size but makes filtering and sampling practical, which usually reduces retained volume overall.
Formula
Log Message Size
Storage = message rate × size × 86,400 × retention days × (1 − compression)
- compression at rest
- Logs are highly repetitive and typically compress 85 to 95 per cent
Worked example
With the default values below, Log Message Size Calculator returns Storage Required of 68.799. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Log messages per secondminimum 0
- 500
- Average message sizeminimum 0 bytes
- 380 bytes
- Retention periodminimum 0 days
- 30 days
- Compression saving at restaccepts 0–100 %
- 85 %
- Storage cost per GB per monthminimum 0
- 0.023
Results
- Storage Required
- 68.799 GB
- Daily Log Volume
- 15.2886 GB
- Storage Before Compression
- 458.658 GB
- Monthly Storage Cost
- $1.58
- Ingest Rate
- 1.5200 Mbps
Step by step
- 1Values used
- 2Log Message Size
- 3Storage Required= 68.799 GB
- 4Daily Log Volume= 15.2886 GB
- 5Storage Before Compression= 458.658 GB
- 6Monthly Storage Cost= 1.58
- 7Ingest Rate= 1.5200 Mbps
Assumptions and limits
- The result is derived only from the 5 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation or tax into account.
- Figures are rounded for display to 4 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Log Message Size calculated?
Storage = message rate × size × 86,400 × retention days × (1 − compression) Log volume is the product of rate, size and retention, and compression at rest cuts it dramatically because logs are highly repetitive. Retention is usually the easiest lever to pull.
Why does Log Message Size matter?
Structured logging increases per-message size but makes filtering and sampling practical, which usually reduces retained volume overall.
What values do I need to enter?
This calculator takes 5 inputs: Log messages per second, Average message size, Retention period, Compression saving at rest, Storage cost per GB per month. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.