I have found the following more detailed information in the TCH Repair Manual concerning the fuel remaining in the tank at certain nominal readings of the fuel gauge. Remember that the tank's nominal capacity is 65 L (~17.2 galUS).

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F(ull) reading corresponds nominally to 62.9 L (~16.6 galUS) in the tank.
Half-full reading corresponds nominally to 35 L (~9.2 galUS) in the tank.
E(mpty) reading corresponds nominally to 7.0 L (~1.8 galUS) in the tank.

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The fuel light comes on when there is nominally 9.8 L (~2.6 galUS) left in the tank.

From this information, I calculate that each minor division on the fuel gauge (there are 16 of them) corresponds to 3.5 L (~0.9 galUS). Moreover, the half-way mark corresponds nominally to precisely half the difference between F and E. [Since the range from Full to Empty is (F - E) = 62.9 - 7 = 56 L (~14.8 galUS), it follows that the Half-way point should be at 28 L above E, i.e. at 7 + 28 = 35 L, which is indeed what Toyota claims.] My experience is that the fuel gauge does indeed read approximately linearly over this range.

According to Toyota's numbers, this also means that there is ~2.1 L (~0.6 galUS) of "overfill" between the F(ull) mark and the nominal tank capacity of 65 L. At the bottom end, it states that, when reading E(mpty), there's nominally still 7.0 L (~1.8 galUS) left in the tank.

Remember that these are only nominal values, so don't rely absolutely on them! But they do give useful ballpark numbers.

Stan