Hydrogen Peroxide Dilution Calculator

Results

Enter your values and press Submit to see mix amounts here.

Calculator

Concentration targets in horticulture

Hydrogen peroxide is often used as an oxidizer for light sanitation and oxygen release. Garden mixes commonly range from 0.05% to 1.0%, depending on contact time, crop sensitivity, and surface load. Lower concentrations suit routine spray bottles, while stronger mixes are reserved for hard surfaces, pots, and non-living equipment. This calculator converts percent or ppm into accurate volumes for repeatable batches.

Measuring accuracy at low doses

At small targets, a tiny measuring error can double the dose. Using ppm helps when you want 100–500 ppm solutions, where 1% equals 10,000 ppm. For precision, measure concentrate with a syringe or graduated cylinder, then dilute into a marked container. If the computed concentrate is below 5 mL, scale up the final volume for easier measuring and better repeatability.

Mixing order and stability

Start with clean water, add the measured peroxide, then top up to the final volume. Gentle mixing reduces splashing and preserves labels on containers. Peroxide decomposes faster in light, heat, and contact with metals or organic debris. Make only what you can use the same day, and store any remainder in an opaque container, tightly capped.

Application considerations for plants and media

Foliar applications work best in cool parts of the day to limit leaf stress. Avoid spraying open blooms and tender seedlings unless you have tested the concentration first. For soil or media, lighter drenches can help reduce odor and biofilm, but repeated strong doses may disturb beneficial microbes. Rinse tools after sanitation if they will contact roots or cuts.

Safety, storage, and recordkeeping

Wear gloves and eye protection, especially with strengths above 6%. Never mix peroxide with acids, bleach, or fertilizers in the same container. Keep concentrates away from children and sunlight. Use the CSV and PDF exports to record strength, target, and batch size so you can reproduce results and compare plant responses over time across seasons and varied conditions. During trials, note weather, cultivar, and any visible leaf spotting.

FAQs

Which peroxide strength should I enter?

Enter the label strength of your product, such as 3%, 6%, 12%, or 35%. If you have a different grade, use that exact percentage for accurate dilution results.

Why does the calculator offer ppm?

ppm helps with very dilute mixes. Since 1% equals 10,000 ppm, you can specify low targets like 200–500 ppm and still get measurable concentrate volumes.

Can I mix peroxide with fertilizers or acids?

Do not combine peroxide with fertilizers, acids, or bleach in the same container. Mix peroxide only with clean water, then apply separately to avoid unsafe reactions or nutrient changes.

How long does a mixed solution stay effective?

Peroxide breaks down with light, heat, and organic debris. For best performance, mix fresh and use the same day. If you must store it, keep it capped in an opaque container.

What if the concentrate amount is very small?

If the required peroxide is under about 5 mL, measuring becomes inaccurate. Increase the final batch size, then use the same ratio. A syringe or pipette also improves precision.

Is hydrogen peroxide safe for all plants?

Sensitivity varies by species and growth stage. Start with lower concentrations, test a small area first, and watch for leaf spotting within 24 hours. Avoid strong mixes on seedlings and open blooms.