Formula
- Use the units shown beside each field.
- Results update automatically whenever you change an input.
- Displayed values use up to four decimal places, or scientific notation for very small or large numbers. Calculations use standard floating-point arithmetic; exact integer and fraction tools identify their own precision rules.
- Average-size planning model. Compression, transaction logs, temporary files and backups are included only if represented in inputs.
Example Calculation
- Rows: 1000000
- Average row bytes: 200 bytes
- Index size relative to data: 50 %
- Free-space allowance: 20 %
- Stored copies: 2
One million 200-byte rows, 50% indexes, 20% free space and two copies require 0.72 GB.
Frequently asked questions
How do I use this calculator?
Enter rows, average row bytes, index size relative to data, free-space allowance, stored copies. The result updates automatically. Use Reset to restore the example values.
What method does it use?
bytes=rows × row bytes × (1+index/100) × (1+free/100) × copies.. Average-size planning model. Compression, transaction logs, temporary files and backups are included only if represented in inputs.
Why might a rounded result differ?
The calculation keeps full numeric precision internally, then rounds the displayed result. Rounding intermediate steps by hand can produce a slightly different answer.
Are my inputs saved online?
No. This calculator processes your inputs in your browser. A recently used list stores only calculator names on this device, not your entered values.
Check the assumptions and units before using this result. Read about calculation methods.