James Richard Fromm
| Indicator | pH Range | pKa | Acid Form | Base Form |
| Methy Violet | 0.0 - 1.6 | 0.8 | Yellow | Blue |
| Thymol Blue | 1.2 - 2.8 | 1.6 | Red | Yellow |
| Methyl Yellow | 29. - 4.0 | 3.3 | Red | Yellow |
| Methyl Orange | 3.1 - 4.4 | 4.2 | Red | Yellow |
| Bromocresol Green | 3.8 - 5.4 | 4.7 | Yellow | Blue |
| Methyl Red | 4.2 - 6.2 | 5.0 | Red | Yellow |
| Chlorophenol Red | 4.8 - 6.4 | 6.0 | Yellow | Red |
| Bromothymol Blue | 6.0 - 7.6 | 7.1 | Yellow | Blue |
| Phenol Red | 6.4 - 8.0 | 7.4 | Yellow | Red |
| Cresol Purple | 7.4 - 9.0 | 8.3 | Yellow | Purple |
| Thymol Blue | 8.0 - 9.6 | 8.9 | Yellow | Blue |
| Phenolphthalein | 8.0 - 9.8 | 9.7 | Colorless | Red |
| Thymolphthalein | 9.3 - 10.5 | 9.9 | Colorless | Blue |
| Alizarin Yellow | 10.1 - 12.0 | 11.0 | Yellow | Red |
| Indigo Carmine | 11.4 - 13.0 | 12.2 | Blue | Yellow |