For chemical leavening: small weight changes alter rise and browning.
1 ounce of Cornstarch in cups
Reviewed by CupOrGram Editorial TeamData methodology: NIST-derived density references + recipe testing notesMethodology
Answer
0.22 cups
Based on cornstarch density of 0.54 g/ml
Source: NIST-DB-72
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Need a substitute for Cornstarch?
We have 3 tested substitutions with exact ratios.
View substitutions →Quick Reference Table
| ounces | cups |
|---|---|
| 1 ounces | 0.22 cups |
| 2 ounces | 0.44 cups |
| 4 ounces | 0.89 cups |
| 8 ounces | 1.8 cups |
| 16 ounces | 3.6 cups |
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Density-accurate conversions for baking
0.22
cups
Science Note: Precision within +/-0.002g
Accuracy: +/-0.002gHow this is calculatedWe multiply the volume by the ingredient's specific density (g/ml) from NIST-standardized reference data. This accounts for how tightly each ingredient packs, giving accuracy within +/-0.002g.Source: NIST-DB-72
Why this conversion matters
Cornstarch has a density of 0.54 g/ml, which means it's moderately light — a cup weighs less than you might expect. Using weight-based measurements gives you consistent results every time.
Recipe Context for Cornstarch
For quick breads: over-leavening can cause collapse after oven spring.
For cookies: balance leavening with acid source for predictable spread.
Common Pitfalls
- Switching brands without re-checking weight can change texture and bake time.
- Using volume-only measurements for dense ingredients can overshoot recipe targets.
- Expired leaveners can underperform even when measured correctly.
Brand Variance Example
Baseline on this page: 1 cup cornstarch = 128g. Real-world range can shift by about 6% because fine powders and leaveners settle during storage, changing cup density.
Example for 2 cups: baseline 256g, common range 240g-272g. If your bake is texture-sensitive, start with the lower bound and adjust after a test batch.