Thyroid Volume Calculator
Enter the three dimensions of each thyroid lobe from ultrasound. The calculator computes the volume using the ellipsoid formula and compares it to gender-specific normal ranges.
Volume = L × W × D × 0.523 (π/6 correction factor per lobe). Total = right lobe + left lobe.
This calculator estimates your total thyroid volume from ultrasound measurements using the ellipsoid approximation method. Enter the length, width, and depth of each thyroid lobe, select your gender, and get the volume in milliliters with a comparison to normal reference ranges.
How It Works
Each thyroid lobe is approximated as an ellipsoid. The volume of each lobe is calculated as length times width times depth times 0.523 (the mathematical constant π/6). The total thyroid volume is the sum of both lobes. The isthmus is typically excluded from standard volume calculations.
Normal Thyroid Volume Ranges
| Gender | Normal Total Volume | Per Lobe (typical) |
|---|---|---|
| Female | Up to 15 mL | 5–10 mL |
| Male | Up to 18 mL | 7–12 mL |
Volumes above these ranges may indicate thyroid enlargement (goiter) and warrant further clinical evaluation. Factors including age, body size, iodine intake, and underlying thyroid disease all influence thyroid volume.
If your doctor ordered a thyroid ultrasound, the report will list three measurements for each lobe. You can enter them here to estimate the total volume. This does not diagnose any condition — bring the result to your physician for interpretation in context.
The ellipsoid method (correction factor 0.523) is the most widely used in clinical practice. The Brunn method uses 0.479. Both are validated approximations. For multinodular glands or irregular morphology, 3D volumetry may be more accurate.
When Thyroid Volume Matters
Thyroid volume measurement is clinically relevant for evaluating suspected goiter, monitoring response to suppressive therapy, assessing iodine deficiency, pre-surgical planning, and tracking changes over serial ultrasound exams. Combined with the TI-RADS calculator for nodule-level risk assessment, these two tools together cover the core thyroid ultrasound measurements.
Source
The ellipsoid formula and normal ranges are based on established clinical references including Brunn et al. (Dtsch Med Wochenschr 1981) and WHO thyroid volume standards. This calculator is for educational purposes only.
Frequently Asked Questions
Does the thyroid volume calculator work for both lobes?
Yes. Enter the length, width, and depth for each lobe separately. The calculator computes the volume of each lobe using the ellipsoid formula and adds them together for the total thyroid volume.
Is my thyroid enlarged if the volume is 22 mL?
For a female patient, a total thyroid volume of 22 mL exceeds the typical normal range of up to 15 mL and would be considered enlarged. For a male patient, it exceeds the typical upper limit of 18 mL. Select your gender in the calculator for an accurate comparison.
Does the thyroid volume calculator account for the isthmus?
No. Standard thyroid volume calculation using the ellipsoid method measures only the right and left lobes. The isthmus is excluded unless its thickness exceeds 3 mm, in which case your radiologist may estimate and add its volume separately.
What is the ellipsoid formula used for thyroid volume?
The ellipsoid formula calculates thyroid lobe volume as length times width times depth times 0.523 (which equals pi divided by 6). Each lobe is treated as an ellipsoid shape. The total thyroid volume is the sum of both lobes.