The “100 times stronger” slogan

You may have seen hypochlorous acid described as “100 times stronger” than bleach. This site does not use that phrase, or any looser version of it, as a claim. This page explains why a single multiplier cannot carry the comparison. It does not try to trace where the number 100 came from; the sources behind this site do not establish that.

What a multiplier like that leaves out

It skips the ppm. Comparisons of this kind only make sense at equal available chlorine, and that is not how either solution is normally used. CDC-cited bleach protocols run from about 100 to 5,000 ppm; the HOCl-type solutions in the studies cited here mostly sit in the tens to a few hundred ppm. When bleach was raised to 150–200 ppm and above, the picture in at least one equal-ppm study changed (Takimoto 2013). See Available chlorine.

It credits the wrong thing. Most of the per-ppm difference between HOCl-type solutions and bleach tracks pH, not the product. In lab studies that lowered bleach’s pH, the results changed in the direction the chemistry predicts, consistent with the larger HOCl share at lower pH (see Same chlorine family, different pH and Mixing, which also explains why that is not a home method).

It ignores everything else that differs. Storage, cost and corrosion do not follow a strength multiplier. Bleach generally holds longer in storage (Shelf life), and a 200 ppm HOCl product rusted steel more than much stronger bleach in one test (Materials and corrosion).

Abstract wording is not a measured result. Some study abstracts use comparative phrases like these, but the review behind this site found no measured comparison that supports repeating them as a finding.

Where to read the comparison instead

For a rated, row-by-row matchup, see HOCl vs bleach and the rated compare table on disinfectant.org.

Sources: CDC 2008, p. 41; Len 2000; Takimoto 2013; Bryant 2026; and the storage and pH sources on Sources.