Calculate corrected QT interval from QT and RR using Bazett, Fridericia, Framingham and Hodges formulas.
ms
sec
STEP 01📈
Enter ECG intervals
Add the measured QT interval and RR interval from the same ECG tracing.
STEP 02🫀
Correct for heart rate
The tool calculates heart rate and applies Bazett, Fridericia, Framingham and Hodges.
STEP 03⚡
Review QTc range
Compare corrected QT values against short, normal, borderline and prolonged ranges.
Bazett QTc
—
Enter details
⚡
Fridericia
—
ms
📐
Framingham
—
ms
🧮
Hodges
—
ms
🫀
Heart Rate
—
beats / min
💓
📸 Your result card is ready
Download a snapshot of your result, share it, or send the link. This tool provides estimates only and is not a substitute for professional medical advice.
ECG Inputs
ms
sec
Formulas use QT and RR in seconds. Values are shown as milliseconds for clinical readability.
QTc Zone
⚡
Hit Calculate to see your result
—
BAZETT QTc ms
<350350–450451–480481–500500+
Short <350Normal 350–450Borderline 451–480Prolonged 481–500High risk 500+
Formula Results
Enter values to see QTc Bazett, Fridericia, Framingham and Hodges.
QTc Metrics
🧮
Metrics appear after calculation
—
Measured QT
—
RR Interval
—
Heart Rate
—
QTc Bazett
—
QTc Fridericia
—
4-Formula Average
LOCAL SMART INSIGHT
✦ Result Explainer
✦
Your explanation appears here
1
—
2
—
i
Use clinical context.
QTc interpretation depends on ECG quality, rhythm, sex, medications, electrolytes and clinical history.
▣ Action Plan
📋
Your plan appears after calculation
◎ What If Simulator
Test how QT or RR changes affect corrected QT values without changing the main result.
—
Calculate your baseline first
● Ask About Your Result
Calculate first, then ask about QTc formulas, heart rate correction or QTc ranges.
Frequently Asked Questions
This calculator includes Bazett, Fridericia, Framingham and Hodges. Each corrects the measured QT interval for heart rate using a different method.
Correction formulas behave differently at slow or fast heart rates. Bazett is widely used but can overcorrect at higher heart rates and undercorrect at lower heart rates.
No. QTc values require clinical interpretation. Diagnosis depends on repeat ECGs, symptoms, family history, medications, electrolytes and clinician assessment.
Medical & Calculation Disclaimer
Results are estimates generated locally in your browser from standard QT correction formulas. They are for informational purposes only and are not medical advice, diagnosis, treatment guidance or a substitute for professional clinical judgement. Abnormal QTc values, fainting, palpitations, medication questions or electrolyte concerns should be reviewed with a qualified healthcare professional. VisionVix accepts no liability for decisions based on this output.
🎁 WELCOME GIFT
🎁 Get 5 FreeAI Credits
Leave your email and get 5 free credits on VisionVix — our AI agent marketplace with 500+ tools. Plus, be first to know when new calculators go live here. No spam, ever.
Credits added to your VisionVix account within 24 hours.
⚡
500+ AI Agents
📊
Smart Calculators
🔔
Early Access
🛡️
No Spam, Ever
🍪 Cookies & analytics
We use Google Analytics cookies to understand how our free tools are used. No ads, no selling data. See our Privacy Policy.
