Bar Soap Dilutions Cheat Sheet

This post originally appeared on Going Green with Lisa Bronner.

Like the forgotten middle child, the Dr. Bronner’s Pure-Castile Bar Soap has languished without a usage cheat sheet for years while the Pure-Castile Liquid Soap and Sal Suds Cleaner hoarded the attention. No more.

Bar soap aficionados, this one’s for you!

Whether you champion the bar soap because of cost, packaging, travel convenience or availability, this Bar Soap Cheat Sheet will help you use the bar soap for almost every purpose as the Pure-Castile Liquid Soap.

Using the bar soap for household cleaning takes a few extra steps. However, I know there are those of you out there whose priorities will gladly swap the extra time.

The main reason I’ve delayed on this cheat sheet is because some of the uses, such as the All-Purpose Spray, require that the soap be liquid. Liquifying bar soap is difficult. That bar wants to stay a bar, which in most circumstances is good. You want your bar of soap to stay solid from first unwrap to final sliver. Who wants a mushy mess on their shower shelf?

The entire time I was trying to liquify the bar, I felt that the bar was fighting back.

The bar soap is not directly a solid version of the liquid soap. They’re very close, as you can read about in my Liquid vs. Bar post, but those few differences, which are designed to make the bar soap hard, make the bar soap very difficult to liquify. It doesn’t melt. (Word to the wise: don’t microwave bar soap.) It doesn’t dissolve readily. However, dissolve it I finally did.

What I produced I have named “soap cream.” It is a white, foamy, thick gel, which thickens further the longer it sits. This liquified bar soap is not the same as the Dr. Bronner’s Liquid Castile Soap. However, it is still soap, cleans well, and disperses in warm water so that it can be diluted for all manner of household applications.

Because the water needed to dissolve the bar soap also dilutes the preservation system, this soap cream will not have the same shelf life as either the bar soap or the liquid soap. After about three weeks, the soap cream thickened so much anyways that it was nearly solid again. I recommend making only as much as you’d use in a couple weeks.

Making Soap Cream

You’d laugh at my first attempt, wherein I plopped a whole bar of soap in a cup of water, just to see what would happen. Hey, if that worked, why make it more complicated? It didn’t work. Here’s what did:

If you have 24 hours:

Dice a bar of soap into ½” cubes. Soak this in 4 cups (960 mL) of water (distilled or reverse osmosis preferred) for at least a day. (In one practice-run, I hit a busy life stretch and let it sit in water for three days. It still worked.) Diced soap in water looks a lot like tofu.

Put the mixture in your blender on low for about 30 seconds or until the soap is fully blended. Do not turn the blender on higher as this will whip excess air into the mixture and increase the volume beyond the capacity of your blender. If you think this process might be too big for your blender, blend half the soap/water at a time. This made 10 – 11 cups of soap cream. Soap Cream looks like beaten, foamy egg whites. Store in air-tight containers. I used mason jars.

If you need it NOW:

This takes more effort on your part, but gets to the end faster with no soak time. Grate a bar of soap on a medium to fine kitchen grater. Combine this with 4 cups (960 mL) warm (not steamy) water in the blender. Blend on low for 30 seconds to a minute.

It is important that the water not be too hot because steam will cause the bubbles in the foam to swell and the volume of your soap cream will increase uncontrollably. When you open your blender, it will continue to grow and pour out all over your counter and down your cabinets and on to your floor. Ask me how I know.

Other forms of Bar Soap mentioned on the Cheat Sheet:

Solid Bar Soap

Some of the purposes on the Bar Soap Cheat Sheet simply use the whole bar. You can rub your washcloth or your toothbrush or your dish brush directly on the bar of soap. I do recommend sectioning off a piece of soap to dedicate for toothbrushing.

Grated Bar Soap

A few usages call for grated bar soap. Use the medium to fine side of a four-sided kitchen grater. Take care not to grate your fingers. I did try using the grating attachment on my food processor. This did not go well. (Cue wide eyes, running footsteps, hiding cats. It was loud and not healthy for my grating attachment.) Keep grated bar soap in an air-tight container. One bar makes about 3 cups (720 mL) of grated bar soap. Grated bar soap looks like cheese.

A few other notes before you get started

If you follow my math listed elsewhere about the soap content of the bar (95%) vs. the liquid (67%), and compare the dilutions of the Bar Cheat Sheet vs. the Liquid Cheat Sheet, the numbers will not match up. I don’t yet have an explanation for that, but I tested these all, and these dilutions are what work best.

All of these are my recommendations from my own experiments using the Dr. Bronner’s Castile Bar. The ratios can easily be adjusted to suit your needs. If you have another recipe or way of doing something, please share it in the comments below. I’m always learning.

Bar Soap Dilutions Cheat Sheet


HANDS-FACE-BODY: Lather Pure-Castile Bar Soap on wet hands or washcloth.

MAKEUP REMOVAL: Wet face and lather bar soap on to hands. Massage into skin. Rinse.

HAIR: Rub wet bar soap into very wet hair. Lather and rinse. Follow with Dr. Bronner’s Citrus Organic Hair Rinse or diluted apple cider vinegar.

BATH: Add 4 Tbsp. (60 mL) grated bar soap or ½ c. (120 mL) soap cream to running warm bath water. (Doesn’t bubble, but still cleans.)

SHAVING: Lather bar on area to create creamy foam. Or, cut to fit as a shaving cake in bottom of shaving cup. Whip up lather with wet shaving brush.

TEETH: Cut a portion of bar to dedicate to toothbrushing. Swipe toothbrush on bar and brush to teeth. Rinse.

FOOT BATH: Add 1 Tbsp. (15 mL) grated bar soap in a small tub of very warmwater. Swish to dissolve.


DISHES (HANDWASHING): Best—Rub dishcloth or brush on bar soap. Or, add 2 Tbsp. (30 mL) grated bar soap or ¼ c. (60 mL) soap cream to about 1 ½ gallons (6 L) very warm running water. Swish to dissolve.

LAUNDRY: Recommended in hot and warm water only. Not recommended for HE. Use Dr. Bronner’s Liquid Castile or Sal Suds in cold water and HE.

•Grated bar soap: In a food processor, combine one grated bar of soap with 4 c. (960 mL) baking soda. Pulse to blend. Use ¼-⅓ c. (60-80 mL) per large load.

•Soap cream: Use ½ c. (120 mL) for a large load. Add ½ c. (120mL) baking soda to wash cycle.

For either method, add 1 c. (240 mL) vinegar to the rinse cycle.

HANDWASHING DELICATES: In 1 gallon (4L) cold water, lather bar soap with hands until the water is slightly soapy. Swish garment gently. Let soak 10 minutes. Swish again. Rinse with clean water. Gently press out excess water with a towel. Hang or lay flat to dry.

MOPPING (WOOD, LAMINATE & STONE FLOORING): Add 1 Tbsp. (15 mL) grated bar soap or ¼ c. (60 mL) soap cream to1 gallon (4 L) hot water. Dunk mop and wring thoroughly. On wood and laminate, avoid excess water.

ALL-PURPOSE CLEANING SPRAY: Dissolve ½ c. (120 mL) soap cream in 3 ½ c. (840 mL) warm water. Whisk to blend. For extra antimicrobial, add ¼ tsp. (1.25 mL) tea tree essential oil.

WINDOWS: Dissolve 1 tsp. (5 mL) soap cream in 1 quart (1 L) warm water in a spray bottle. Spray window and squeegee. Follow with spray of club soda or vinegar/water. Wipe dry.

TOILET: Spray toilet bowl thoroughly with All-Purpose Spray (above) with optional ¼ tsp. (1.25 mL) tea tree oil added. Sprinkle baking soda on toilet brush, scrub bowl, let sit 10 minutes, flush.


FRUIT & VEGGIE WASH: Lather bar soap with hands into a bowl of water. Dunk produce and swish. Rinse in clear water.

DOG WASHING: Wet dog thoroughly. Massage bar in fur to create good lather. Rinse thoroughly. As with people, avoid soap in eyes and water in ears.

CLEANING MAKEUP BRUSHES: Wet makeup brush thoroughly. Lather soap in hands and massage gently through bristles for 10+ seconds. Rinse and air dry.

ANT SPRAY (NOT ON PLANTS): Dissolve ½ c. (120 mL) soap cream in 3 ½ c. (840 mL) of water.

Author Profile
Lisa Bronner

Lisa Bronner is a prolific writer, consumer advocate, and speaker on health and green lifestyle issues. She is author of the blog, “Going Green with a Bronner Mom,” and granddaughter of Dr. Emanuel Bronner, founder of Dr. Bronner’s.

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