Round to the Nearest Tenth Calculator
Enter any number to get it rounded to the nearest tenth (0.1), with the tenths above and below shown on a number line.
Your number rounded to 1 decimal place (nearest 0.1)
- 1
Shift decimal one place right
3.14159 × 10 = 31.4159 - 2
Round to nearest integer
round(31.4159) = 31 - 3
Restore decimal (÷ 10)
31 ÷ 10 = 3.1
How does this calculator work?
Multiply by 10, round to the nearest integer (half-up), divide by 10. For 3.14159: 31.4159 → 31 → 3.1. For 3.75: 37.5 → 38 → 3.8. The result always has at most 1 decimal place and differs from the original by no more than 0.05.
Formula
How this is calculated
Rounding to the nearest tenth means keeping exactly one decimal place. The method multiplies by 10 to shift the tenths digit into the ones column, applies half-up rounding to select the nearest whole number, then divides by 10 to restore the scale. For example, 3.14159 × 10 = 31.4159 rounds to 31, giving 3.1. For 3.75, 37.5 rounds to 38, giving 3.8.
The rounding error is the absolute difference between the original value and the result; it is always at most 0.05 (half a tenth). The "tenth below" is the largest multiple of 0.1 that does not exceed your number (floor to nearest tenth), and the "tenth above" is the smallest multiple of 0.1 that is not less than your number (ceiling to nearest tenth). The rounded answer equals whichever of these two is closer.
Rounding to one decimal place is standard across many practical fields: body temperatures (36.6 °C), sprint times (9.8 s), heights and distances. Because the calculation relies on binary floating-point arithmetic, a small number of values near the exact midpoint may round in an unexpected direction — for example 3.65 may be stored as 3.6499999… and round down to 3.6 rather than up to 3.7.
Frequently asked questions
3.14159 rounded to the nearest tenth is 3.1. The second decimal digit (4) is less than 5, so the tenths digit stays at 1.
3.75 rounded to the nearest tenth is 3.8. The second decimal digit (5) meets the half-up threshold, so the tenths digit rounds up from 7 to 8.
Yes — a tenth is 1/10 = 0.1, so "nearest tenth" and "one decimal place" describe exactly the same operation.
Also known as
TG we-Calculate Editorial Team. (2026). Round to the Nearest Tenth Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/round-to-the-nearest-tenth-calculator
TG we-Calculate Editorial Team. "Round to the Nearest Tenth Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/round-to-the-nearest-tenth-calculator.
TG we-Calculate Editorial Team, "Round to the Nearest Tenth Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/round-to-the-nearest-tenth-calculator
@misc{wecalculate_round_to_the_nearest_tenth_calculator, title = {Round to the Nearest Tenth Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/round-to-the-nearest-tenth-calculator}}, year = {2026}, note = {TG we-Calculate} }
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