Process Manufacturing calculator
Solids Content Calculator
Turn a dry-down test into percent solids and see whether the batch meets spec. You need the wet and dry sample weights, the batch weight, and the target solids with its tolerance.
What this calculator does
- Percent solids from a dry-down test, checked against your spec, with the liquid or solids that bring the batch to target.
Formula used
- Solids content = dry residue mass ÷ wet sample mass × 100
- Deviation = solids content − target solids; spec margin = tolerance − |deviation|
- Dry solids in batch = batch mass × solids content ÷ 100
- Below target: liquid to remove = batch mass × (1 − solids ÷ target); dry solids to add = batch mass × (target − solids) ÷ (100 − target)
- Above target: liquid to add = batch mass × (solids ÷ target − 1)
Inputs explained
- Wet Sample Mass: Sample weight before drying, dish tare subtracted.
- Dry Residue Mass: Residue weight after drying to constant weight, dish tare subtracted.
- Batch Mass: Batch the sample came from, weighed by scale or load cells.
- Target Solids: Solids content on the spec or formula sheet.
- Spec Tolerance, Plus or Minus: Allowed deviation either side of target, in percentage points.
How to use the result
- Best suited to releasing a coating or adhesive batch against spec, standardizing a slurry before transfer.
- Bound water and volatile solids shift the result, so follow your method's oven temperature and drying time. A press or centrifuge whose filtrate carries solids must remove more liquid than shown here.
Current U.S. benchmarks
- The producer price index for industrial chemicals stands at 336.006 (BLS, Aug 2026), up 13.3% from a year earlier. Quotes priced off last quarter's material cost miss this move.
- The U.S. has 14,543 chemical manufacturing establishments employing about 911,245 workers (Census County Business Patterns, 2023).
Common questions
- How long do I dry a sample for total solids? Until the weight stops changing, at the temperature your method sets. EPA Method 1684 dries sludge at 103 to 105 °C for at least 12 hours. It then reheats until the weight changes less than 4% or 50 mg, whichever is less.
- Is percent solids the same as 100 minus moisture? Yes, when moisture is reported on a wet basis: solids plus everything lost in drying make up the whole sample. At 42% solids the sample is 58% water and other volatiles. Report whichever figure your spec names.
- Should I remove liquid or add solids to raise percent solids? Remove liquid when your formula's solids ratios must stay fixed; that takes an evaporator, thickener or press. Adding dry solids changes the formula unless the solids are one material. The calculator gives both amounts so you can compare them.
- Why do my duplicate solids tests disagree? Check the sampling first. EPA Method 1684 warns that subsampling multi-phase samples can introduce serious errors and asks that samples stay homogeneous. Dried residues also absorb moisture quickly, so weigh them straight from the desiccator.
Related guides
Last reviewed 2026-10-01.