Cut the peeled daikon in half lengthwise (if your daikon is very large, cut the halves in half again, to form wedges), and into ¼-inch half-moons. Toss the daikon with ¼ cup kosher salt in a bowl or colander, and let sit for 3 hours, uncovered at room temperature. Rinse the daikon with cold water and drain any excess water. Pack the salted daikon into a large jar or other airtight container.
Combine ½ cup sugar, ½ cup rice vinegar, and ½ teaspoon turmeric together in a small saucepan and bring it to a boil. Turn off the heat and stir until the sugar is completely dissolved. Cool the vinegar mixture slightly while the daikon sits. Pour the sugar-vinegar mixture into the jar with the daikon. Note that the vinegar mixture should completely cover the daikon. If it doesn't, you may need to mix up a little more vinegar-sugar mixture, using a 1:1 ratio (there is no need to add additional turmeric).
Refrigerate the daikon for at least 3 days before serving. It will keep in the fridge for up to a month.
Notes
An updated note on brine volume
I recently (June 2026) re-tested this recipe after receiving several comments that the volume of brine was not nearly enough to cover 2½ pounds of daikon. While I initially thought that the amount of brine would be too little to cover the daikon, after salting it, I was reminded that it loses a lot of water and shrinks.I poured the brine over the salted daikon, and after pressing the daikon down, it was fully submerged with room to spare. While my daikon wasn't quite a full 2.5 pounds, I think it would have been enough to just cover 2.5 pounds.An actual photo of approximately 2.25lbs daikon, after salting, fully submerged in the amount of brine listed in the recipe.That being said, if you don't want to fuss with worrying about whether the volume of brine will be enough, and/or having to press down the daikon, simply make a little more brine. Double will certainly be enough, but even a 1.5 times recipe (there is no need to add additional turmeric, so you'll be using ¾ cups of each sugar and rice vinegar, and ½ teaspoon turmeric) will do the job.