How much consumption tax is inside a ¥1,980 tax-included price? What is the tax-included total if you add 10% to a net price? Japanese consumption tax answers change depending on whether the figure is tax-included or tax-excluded, whether the rate is 8% or 10%, and how you round the fraction — and reaching for a calculator every time is a small but constant chore. This consumption tax calculator takes a single amount and a choice of whether it is tax-excluded or tax-included, then shows the net price, the tax amount, and the tax-included total at once. For a tax-excluded input it adds the tax on top to give the gross; for a tax-included input it pulls the tax back out to give the net. You can switch with one tap between the reduced 8% rate (used for food, non-alcoholic groceries, and newspapers) and the standard 10%, and you can type any custom rate (such as the old 5% or 8%). The tax fraction can be floored (the default, common in retail), ceiled, or rounded to the nearest yen. The net, tax, and gross always add up exactly, because the tax is rounded first and the other figure is derived from it — so you can use the breakdown directly on a receipt or invoice. Everything is computed only inside your browser; the amount you enter is never sent to any server.