BMR Reference for Age 30
Basal metabolic rate at age 30 is not one number — it is a range set by height and weight. This page holds the formula inputs steady at age 30 and sweeps body composition instead: four BMI levels, men at 175 cm and women at 165 cm, each estimated with both Mifflin-St Jeor and Harris-Benedict so the spread between the classic equations is visible at a glance.
Held at the same 76.6 kg, the age-29 page reads 1720 kcal against the 1715 here — 5 kcal below, which is exactly the 5 kcal the Mifflin-St Jeor age term removes per birthday. Harris-Benedict sits 69 kcal higher on that row, a 4.0% band. Across the five activity levels the same body spans 2,058 to 3,259 kcal — 1,201 kcal, against just 310 kcal that the age term strips out between 18 and 80.
BMR at age 30 by body composition
| BMI | Men (175 cm) | Women (165 cm) | ||||
|---|---|---|---|---|---|---|
| Weight | Mifflin | Harris | Weight | Mifflin | Harris | |
| 20 | 61.3 kg | 1562 kcal | 1579 kcal | 54.5 kg | 1265 kcal | 1333 kcal |
| 25 | 76.6 kg | 1715 kcal | 1784 kcal | 68.1 kg | 1401 kcal | 1459 kcal |
| 30 | 91.9 kg | 1868 kcal | 1989 kcal | 81.7 kg | 1537 kcal | 1584 kcal |
| 35 | 107.2 kg | 2021 kcal | 2194 kcal | 95.3 kg | 1673 kcal | 1710 kcal |
From BMR to daily burn: TDEE at age 30
Multiplying BMR by an activity factor gives total daily energy expenditure. The factors below are the same five levels the main calculator offers, applied to the BMI-25 man from the table (76.6 kg, BMR 1715 kcal):
| Activity level | Factor | TDEE |
|---|---|---|
| Sedentary — little or no exercise | ×1.2 | 2058 kcal/day |
| Lightly active — 1–3 days/week | ×1.375 | 2358 kcal/day |
| Moderately active — 3–5 days/week | ×1.55 | 2658 kcal/day |
| Very active — 6–7 days/week | ×1.725 | 2958 kcal/day |
| Extra active — intense daily training | ×1.9 | 3259 kcal/day |
Get your own figure
Body size matters more than any reference table can capture, so a two-minute personal estimate is usually worth more than a row of averages. Enter your numbers and the box computes the Mifflin-St Jeor result with the same coefficients used across this site:
Frequently asked questions
What is the BMR of a 30-year-old?
It depends on body size as well as age. At age 30, a 175 cm man weighing about 76.6 kg has a Mifflin-St Jeor BMR of roughly 1715 kcal per day, while a 165 cm woman at 68.1 kg lands near 1401 kcal per day. The table above shows how the estimate moves across four common body-composition levels.
Why does BMR fall as age increases?
The Mifflin-St Jeor equation subtracts 5 kcal for every year of age, so between age 20 and age 80 the estimate drops by about 300 kcal per day at the same height and weight. The coefficient is a population average: body composition, not the birthday itself, drives most of the real change.
Mifflin-St Jeor or Harris-Benedict — which should I use?
Mifflin-St Jeor is the default on this site because validation studies found it tracks measured resting energy expenditure more closely for most adults. Harris-Benedict, shown beside it in the table, runs higher for many people — often by 5 to 10 percent — so comparing the two columns is a quick way to see the uncertainty band around any single number.
Nearby ages
Want the full picture — Katch-McArdle from body-fat percentage, the age chart and TDEE in one run? Open the BMRScope calculator or browse every age page.