510 ppb to ppm

510 ppb = 0.51 ppm

ppbppm
495 ppb0.495
500 ppb0.5
505 ppb0.505
5100.51
515 ppb0.515
520 ppb0.52
525 ppb0.525

510 ppb = 0.51 ppm

Formula

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