ACR TI-RADS Thyroid Nodule Calculator
The ACR TI-RADS (Thyroid Imaging Reporting and Data System) 2017 assigns points to five ultrasound features of a thyroid nodule — composition, echogenicity, shape, margin, and echogenic foci — to assign a risk level from TR1 (benign) to TR5 (highly suspicious) and guide FNA recommendations.
Composition
Echogenicity
Shape
Margin
Echogenic foci
Total ACR TI-RADS points — higher = more suspicious
- 1
Composition + Echogenicity
2 + 1 = 3 - 2
Shape + Margin + Echogenic foci
0 + 0 + 0 = 0 - 3
Total TI-RADS points
3 + 0 = 3
How does this calculator work?
ACR TI-RADS 2017 scores five ultrasound features (composition + echogenicity + shape + margin + echogenic foci). Score 0 = TR1 (benign); 1–2 = TR2 (< 2% malignancy); 3–4 = TR3 (< 5%); 5–6 = TR4 (5–20%); ≥ 7 = TR5 (> 20%). Each level has size thresholds that trigger FNA biopsy recommendation.
Formula
How this is calculated
The ACR TI-RADS lexicon (Tessler et al., Radiology 2017) assigns 0–3 points to each of five ultrasound feature categories: composition (0 for cystic/spongiform, 1 for mixed, 2 for solid); echogenicity (0 anechoic, 1 hyperechoic/isoechoic, 2 hypoechoic, 3 very hypoechoic); shape (0 wider-than-tall, 3 taller-than-wide); margin (0 smooth or ill-defined, 2 lobulated/irregular, 3 extra-thyroidal extension); and echogenic foci (0 none or large comet-tail, 1 macrocalcifications or rim calcifications, 3 punctate echogenic foci). The points are summed to a total that maps to a risk level: TR1 = 0 pts (benign, 0% malignancy risk); TR2 = 2 pts (not suspicious, < 2%); TR3 = 3–4 pts (mildly suspicious, < 5%); TR4 = 5–6 pts (moderately suspicious, 5–20%); TR5 = ≥ 7 pts (highly suspicious, > 20%).
Each TI-RADS level has size-based FNA thresholds. TR3: FNA if the largest diameter ≥ 2.5 cm, follow if ≥ 1.5 cm. TR4: FNA if ≥ 1.5 cm, follow if ≥ 1 cm. TR5: FNA if ≥ 1 cm, follow if ≥ 0.5 cm. TR1 and TR2 require no FNA or follow-up in most guidelines. These thresholds reflect the 2017 ACR guidelines; local protocols may vary.
This calculator implements the ACR TI-RADS 2017 system. Other national TI-RADS systems (e.g. EU-TIRADS, K-TIRADS) use different scoring rules. Always confirm the system used by the reporting radiologist before applying management thresholds.
Frequently asked questions
A nodule is considered "taller than wide" (also called non-parallel orientation) when its anterior-posterior (AP) diameter is greater than its transverse diameter on a transverse view, or when the AP diameter exceeds the cranio-caudal diameter on a longitudinal view. This shape is strongly associated with malignancy (3 points in TI-RADS) because carcinomas tend to grow across fascial planes rather than conforming to tissue planes.
Punctate echogenic foci (PEF) are small, pinpoint bright spots without posterior acoustic shadowing. They are the sonographic correlate of psammomatous microcalcifications and are highly specific for papillary thyroid carcinoma, earning 3 points in the TI-RADS system. They should be distinguished from comet-tail artefacts (which indicate colloid, a benign finding) and from macrocalcifications (which cast posterior acoustic shadows).
For TR3 nodules below the FNA threshold, ACR TI-RADS 2017 recommends ultrasound follow-up at 1, 3, and 5 years. If the nodule shows significant growth (≥ 20% increase in two or more dimensions) or develops new suspicious features at follow-up, FNA should be reconsidered regardless of absolute size. Nodules that remain stable for 5 years can generally be discharged from surveillance.
Also known as
TG we-Calculate Editorial Team. (2026). ACR TI-RADS Thyroid Nodule Calculator [Online calculator]. TG we-Calculate. https://we-calculate.com/calculator/tirads-calculator
TG we-Calculate Editorial Team. "ACR TI-RADS Thyroid Nodule Calculator." TG we-Calculate. 2026. https://we-calculate.com/calculator/tirads-calculator.
TG we-Calculate Editorial Team, "ACR TI-RADS Thyroid Nodule Calculator," TG we-Calculate, 2026. [Online]. Available: https://we-calculate.com/calculator/tirads-calculator
@misc{wecalculate_tirads_calculator, title = {ACR TI-RADS Thyroid Nodule Calculator}, author = {{TG we-Calculate Editorial Team}}, howpublished = {\url{https://we-calculate.com/calculator/tirads-calculator}}, year = {2026}, note = {TG we-Calculate} }
Did this calculator help you?