---
title: "T4 Thyroxine Total Test: What It Measures, What Results Mean"
description: "It measures total thyroxine (T4) in your blood to help assess thyroid function, with convenient ordering and results through Vitals Vault/Quest."
canonical: "https://www.vitalsvault.com/biomarkers/t4-thyroxine-total"
last-updated: 2026-08-22
---

# T4 Thyroxine Total Test: What It Measures, What Results Mean

> It measures total thyroxine (T4) in your blood to help assess thyroid function, with convenient ordering and results through Vitals Vault/Quest.

---

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