What the two forms are
Creatine monohydrate is a creatine molecule bonded to one water molecule. It's 88% creatine by weight, so 5 g of powder delivers 4.4 g of creatine. It's the form used in more than 700 published trials, including nearly every study behind the doses on this site.
Creatine HCl is creatine bonded to hydrochloric acid, making a salt. Chloride is heavier than water, so HCl is about 78% creatine by weight: 5 g of powder delivers 3.9 g. Its selling point is solubility. Lab measurements put HCl at roughly 38 times more soluble in water than monohydrate, which is why it disappears in a glass while monohydrate leaves a gritty bottom.
Does better solubility mean better absorption?
This is the whole argument, and it fails on one number: monohydrate is already absorbed almost completely. Tracer studies put oral bioavailability at around 99%. The grit at the bottom of the glass isn't lost creatine; it dissolves in your stomach within minutes. There is no absorption gap for HCl to close. The manufacturers' claim that you can take a much smaller dose because "more gets in" would require monohydrate to be poorly absorbed, and it isn't.
The head-to-head trials
| Study | Design | Result |
| França et al. 2015 | 36 trained men, 4 weeks: 5 g monohydrate/day vs 1.5 g HCl/day vs placebo (HCl at the label micro-dose) | All three groups gained strength; small, inconsistent differences; no muscle creatine measured. Often cited for HCl, but the placebo group improved too, and 1.5 g/day is below any dose known to saturate muscle. |
| Eghbali et al. 2024 | 40 men, 8 weeks, resistance training: equal-creatine doses of monohydrate vs HCl vs placebo | Both forms improved strength and lean mass over placebo; no difference between forms. |
That's the full evidence base: one underpowered study that didn't measure the thing that matters, and one properly dosed study that found the forms are the same. No trial has ever shown HCl raising muscle creatine more than monohydrate at equal creatine doses, and no trial has shown the 750 mg "micro-dose" working at all.
Equivalent doses
Because the two powders carry different amounts of creatine per gram, matching them means matching the creatine, not the scoop:
| Creatine delivered | Monohydrate needed | HCl needed |
| 2.6 g (3 g mono) | 3.0 g | 3.4 g |
| 4.4 g (5 g mono) | 5.0 g | 5.6 g |
| 0.6 g ("750 mg per 100 lb" HCl label dose) | 0.7 g | 0.75 g |
The ISSN's effective maintenance range is 3–5 g of creatine monohydrate per day (about 2.6–4.4 g of creatine). If you use HCl, take the same 3–5 g of powder, or slightly more, not the 750 mg on the label. Our dosage calculator gives a body-weight dose that applies to either form.
Stomach upset and bloating
The strongest practical argument for HCl is digestive. At loading doses (20–25 g/day of monohydrate), some people get stomach cramps or diarrhea, and a smaller, fully dissolved dose might sit better. At maintenance doses this is rarely an issue with either form, and the fixes for monohydrate are cheap: take it with a meal, use warm liquid, or split 5 g into two doses. Note that the muscle water gain is identical for any form, because it comes from creatine filling muscle stores, not from the salt it's attached to. "HCl doesn't cause water retention" is only true at doses too small to fill the stores.
Price per gram of creatine
| Form | Typical price (Sept 2026) | Creatine per gram of powder | Cost per gram of creatine |
| Monohydrate, 1 kg tub | $30–40 | 0.88 g | ≈ $0.04 |
| Monohydrate, micronized 500 g | $25–35 | 0.88 g | ≈ $0.07 |
| Creatine HCl, 120 g tub | $40–55 | 0.78 g | ≈ $0.50–0.60 |
At a real 4–5 g/day, HCl costs about $2 a day versus 20 cents. The small tubs only look reasonable because they assume the 750 mg dose that has no evidence behind it.
Who might still pick HCl
Someone who genuinely can't tolerate monohydrate even at 3 g with food and split doses, and doesn't mind paying ten times more. That's a small group. For everyone else, micronized monohydrate (finer grind, dissolves better than standard) solves the grit, costs cents a day, and is the form every dose on this site is built on.
Calculate my dose (works for either form) →
Frequently asked questions
Is creatine HCl better than monohydrate?
No measured outcome says so. Equal strength and muscle gains in the 2024 head-to-head; monohydrate has 700+ trials and costs a tenth as much.
How much HCl equals 5 g of monohydrate?
About 5.6 g of HCl powder, because HCl is 78% creatine vs 88%.
Does the 750 mg HCl dose work?
No trial supports it. It delivers about 0.6 g of creatine, well below the 2.6–4.4 g maintenance range.
Does HCl cause less water retention?
Not at equal creatine doses. The water is from filling muscle stores, whichever form fills them.
Does HCl cause less bloating?
Possibly during loading. At maintenance doses, monohydrate with food is fine for nearly everyone.
Should I load with HCl?
Loading is optional for any form. If you do, use the same 0.3 g/kg of creatine; see the loading calculator.
Sources
- Kreider RB, et al. ISSN position stand: safety and efficacy of creatine supplementation (section on alternative forms). J Int Soc Sports Nutr 2017.
- Jäger R, et al. Analysis of the efficacy, safety, and regulatory status of novel forms of creatine. Amino Acids 2011.
- Gufford BT, et al. Physicochemical characterization of creatine N-methylguanidinium salts (solubility of creatine HCl). J Diet Suppl 2010.
- França E, et al. Creatine HCl and creatine monohydrate improve strength but only creatine HCl induced changes on body composition in recreational weightlifters. Food Nutr Sci 2015.
- Eghbali E, et al. Creatine monohydrate vs creatine hydrochloride with resistance training: an 8-week randomized trial. 2024.