TI-RADS Calculator – Thyroid Nodule Assessment
Calculate ACR TI-RADS score for thyroid nodules from ultrasound characteristics to assess malignancy risk and guide management.
Select the ultrasound features of the thyroid nodule and optionally enter its size to get the TI-RADS level, risk category, and recommended action.
TI-RADS Calculator – Thyroid Nodule Assessment
Calculate ACR TI-RADS score for thyroid nodules from ultrasound characteristics to assess malignancy risk and guide management.
TI-RADS Assessment
Total Score0
TI-RADS LevelTR1 – Benign
Malignancy RiskNo suspicious features
Recommended Action: No FNA needed; no follow-up required
About the TI-RADS calculator
The Thyroid Imaging Reporting and Data System (TI-RADS) is a standardised framework developed by the American College of Radiology (ACR) to evaluate thyroid nodules detected on ultrasound and stratify their risk of malignancy. Thyroid nodules are extremely common, found incidentally in up to 50–70% of adults undergoing neck imaging, yet the vast majority — over 90% — are benign. TI-RADS provides a structured scoring system that helps clinicians decide which nodules need fine-needle aspiration (FNA) biopsy and which can simply be monitored with periodic ultrasound.
The ACR TI-RADS scoring system assigns points to five ultrasound features. Composition refers to the proportion of solid versus cystic content: cystic or spongiform nodules score 0 points, mixed nodules score 1 point, and solid nodules score 2 points. Echogenicity describes how the nodule appears relative to surrounding thyroid tissue: anechoic nodules score 0, hyperechoic or isoechoic nodules score 1, hypoechoic nodules score 2, and very hypoechoic nodules score 3. Shape scores 0 for wider-than-tall orientation or 3 for taller-than-wide orientation, which is a suspicious feature. Margin scores 0 for smooth or ill-defined margins, 2 for lobulated or irregular margins, and 3 for extra-thyroidal extension. Echogenic foci scores 0 for none or large comet-tail artifacts, 1 for macrocalcifications, 2 for peripheral rim calcifications, and 3 for punctate echogenic foci.
The total point score maps to a TI-RADS category. TR1 (0 points) indicates benign appearance and requires no further workup. TR2 (2 points) indicates not suspicious, with less than 2% malignancy risk and no follow-up needed. TR3 (3 points) indicates mildly suspicious, warranting FNA for nodules 2.5 cm or larger and surveillance ultrasound for those 1.5 cm or larger. TR4 (4–6 points) indicates moderately suspicious, with 5–20% malignancy risk, triggering FNA for nodules 1.5 cm or larger. TR5 (7 or more points) indicates highly suspicious, with greater than 20% malignancy risk, warranting FNA for nodules 1 cm or larger.
TI-RADS is not a diagnosis of cancer — it is a risk-stratification tool. FNA biopsy and subsequent pathological assessment are required for definitive tissue diagnosis. The system is intended to reduce unnecessary biopsies of clearly benign nodules while ensuring appropriate evaluation of those with concerning features. Clinicians should integrate TI-RADS findings with the patient's clinical history, thyroid function tests, and risk factors such as prior radiation exposure or family history of thyroid cancer.
TI-RADS scoring examples
Three nodule scenarios illustrating how ultrasound features combine to produce a TI-RADS score and management recommendation.
| Ultrasound Features | Score / Level | Recommendation |
|---|---|---|
| Spongiform, anechoic, wider-than-tall, smooth margin, no foci | 0 pts — TR1 | Benign appearance. No FNA required, no routine follow-up needed. |
| Solid, hypoechoic, wider-than-tall, smooth margin, no foci | 4 pts — TR4 | Moderately suspicious. FNA recommended if nodule ≥ 1.5 cm. |
| Solid, very hypoechoic, taller-than-wide, irregular margin, punctate foci | 13 pts — TR5 | Highly suspicious. FNA if ≥ 1 cm. Follow-up ultrasound if 0.5–1 cm. |
How to use the TI-RADS calculator
- Review the ultrasound report and identify the values for each of the five ACR TI-RADS features: composition, echogenicity, shape, margin, and echogenic foci.
- Select the appropriate option for each feature from the dropdown menus; the point value for each selection is shown next to the option label.
- Optionally enter the largest dimension of the nodule in centimetres to receive a size-based management recommendation.
- Click Calculate to see the total point score, TI-RADS category (TR1–TR5), estimated malignancy risk, and recommended action.
- Share the result with your radiologist or endocrinologist — TI-RADS is a decision-support tool and should always be interpreted in the context of the full clinical picture.
TI-RADS calculator FAQ
What is TI-RADS and who developed it?
TI-RADS (Thyroid Imaging Reporting and Data System) was developed by the American College of Radiology (ACR) and published in 2017. It provides a standardised lexicon and scoring system for thyroid nodules on ultrasound, similar to BI-RADS for breast imaging. The ACR TI-RADS version is distinct from earlier versions developed by other groups.
What does each TI-RADS level mean?
TR1 (benign) and TR2 (not suspicious) require no biopsy or routine follow-up. TR3 (mildly suspicious) and TR4 (moderately suspicious) require FNA or surveillance depending on nodule size. TR5 (highly suspicious) carries more than 20% malignancy risk and requires FNA for nodules of 1 cm or larger. The cut-offs balance sensitivity for cancer detection against avoidance of unnecessary procedures.
Is TI-RADS score the same as cancer risk percentage?
No. The TI-RADS score is a point total that maps to a risk category with an associated approximate malignancy risk range. TR3 carries less than 5% risk, TR4 carries 5–20%, and TR5 carries more than 20%. The actual risk for any individual nodule depends on additional clinical factors and is only definitively determined by biopsy.
What is a spongiform nodule?
A spongiform nodule is composed almost entirely of small cystic spaces, giving it a sponge-like appearance on ultrasound. Spongiform nodules carry an extremely low risk of malignancy and score 0 points for composition in the ACR TI-RADS system, often resulting in a TR1 or TR2 classification regardless of other features.
Do all nodules with a high TI-RADS score need surgery?
No. A high TI-RADS score triggers a recommendation for FNA biopsy, not surgery. Surgery is indicated only after biopsy confirms malignancy (Bethesda categories V–VI) or when the cytology result is indeterminate (Bethesda III–IV) and molecular testing or clinical judgement favours resection. Many TR4 and TR5 nodules prove benign on biopsy.
Can TI-RADS be used for children?
The ACR TI-RADS criteria were developed for adults. Thyroid nodules in children are relatively uncommon but carry a higher malignancy rate (20–26%) than in adults. Paediatric thyroid nodule guidelines from the American Thyroid Association and paediatric endocrine societies have lower size thresholds for biopsy. Consult a paediatric endocrinologist for children with thyroid nodules.