455 ppb to ppm

455 ppb = 0.455 ppm

ppbppm
440 ppb0.44
445 ppb0.445
450 ppb0.45
4550.455
460 ppb0.46
465 ppb0.465
470 ppb0.47

455 ppb = 0.455 ppm

Formula

1 ppm = 1 mg/L (aqueous, density ≈ 1 kg/L) · 1 ppb = 0.001 mg/L · 1% = 10,000 ppm