Substrate Hydration Calculator
Four quick ways to compute water, dry, and total weights. Use any units (g, kg, lb) — just keep them consistent within a calculation.
- Total + Water % → returns water & dry amounts.
- Dry + Water % → returns total & water amounts.
- Water + Dry → returns water %.
- Total + Dry → returns water % & water weight.
Typical sawdust blocks land around 58–62% water; adjust for your substrate, species, and workflow.
① Start with Total Weight
Enter the finished block weight and desired water percentage.
Inputs
Use grams (or any unit) consistently.
%
Typical blocks: 58–62%.
Results
Calculated from total × (water% ÷ 100).
② Start with Dry Weight
Enter dry weight and target water percentage to get the finished block.
Inputs
%
Results
Total = dry ÷ (1 − water%/100).
③ Water + Dry → Water %
Provide water and dry weights to compute the water percentage.
Inputs
Results
%
Water% = water ÷ (water + dry) × 100.
④ Total + Dry → Water % & Water Weight
Enter the combined total and the dry-only amount.
Inputs
Results
%
Water = total − dry; Water% = water ÷ total × 100.
Frequently Asked Questions
What units should I use?
Any units (g, kg, lb, oz) are fine as long as you use the same unit within a single calculation.
What water percentage should I target?
Many sawdust blocks land around 58–62% water, but you should adjust based on your substrate, species, and technique.
Can I copy results?
Yes. Each calculator has an icon-only “copy” button and outputs are in read-only fields that are easy to select and copy.