Result
Therapeutic Index Calculator
The Therapeutic Index Calculator is a helpful online tool for pharmacy students and researchers. It makes it easy to understand how safe a drug is. You can calculate the therapeutic index in seconds using this tool.
This tool is free to use and works on all devices. It’s designed to be simple, fast, and student-friendly. It helps you save time and avoid mistakes.
Let’s break down what the tool does, how it works, and why it’s useful for your studies.
What Is the Therapeutic Index?
The therapeutic index (TI) shows how safe a drug is. It compares the dose that causes harm to the dose that gives a therapeutic effect.
The basic formula is:
Therapeutic Index (TI) = LD50 / ED50
LD50 is the dose that kills 50% of the test group.
ED50 is the dose that works for 50% of the test group.
Sometimes, you may use TD50 instead of LD50. TD50 is the dose that causes toxicity in 50% of people. This is useful when testing drugs on humans, where lethal dose data is not available.
A higher TI means the drug is safer. A lower TI means the drug must be used more carefully.
What This Tool Does
This Therapeutic Index Calculator lets you enter values for:
LD50 (or TD50)
ED50
You can choose the unit of measurement that suits your data. Whether you’re using mg/kg, mg/m², or any custom unit, the tool adapts.
Once you enter the values, the tool:
Calculates the exact therapeutic index
Shows a color-coded safety interpretation
Displays a bar graph comparing LD50 and ED50
Provides tooltip explanations for every key term
Key Features of the Tool
✅ Smart Input Validation
The tool only accepts numbers for inputs. It stops you from entering text or negative values. LD50/TD50 and ED50 must be greater than zero. This helps avoid calculation errors.
✅ Optional TD50 Support
If you don’t have LD50 data, no problem. You can enter TD50 instead. The tool will still calculate the therapeutic index.
✅ Unit Selection and Custom Units
You can choose from common units like mg/kg, or type your own unit. The result and graph will reflect your chosen unit.
✅ Tooltip Definitions
Not sure what LD50 or ED50 means? Just hover or tap on the tooltips next to the fields. The tool explains each term in simple language. This is great for students who are still learning.
✅ Responsive Graph with Chart.js
The tool draws a clean bar graph using Chart.js. It compares LD50 (or TD50) and ED50 visually. This helps you see the drug’s safety margin at a glance.
The graph resizes on all screen sizes, so you can use it on a phone, tablet, or laptop.
✅ Interpretation with Badge Colors
The tool also interprets the therapeutic index value. It uses color-coded badges:
🟢 Green = Safe (TI > 10)
🟡 Yellow = Moderate caution (TI between 3 and 10)
🔴 Red = High risk (TI < 3)
This helps you understand the result instantly, without complex math.
✅ Reset Button
Made a mistake? Want to start over? Just click the reset button to clear everything and begin again.
✅ Export Options
You can export your work in two ways:
PNG – Save just the graph as an image.
PDF – Download a file with your input values, TI result, and graph.
This is useful for lab reports, presentations, or study notes.
Why This Tool Is Useful
If you’re a pharmacy or pharmacology student, this tool will help you understand drug safety better. It removes the confusion of manual formulas and lets you focus on the result.
It’s perfect for:
Lab work
Homework
Exam prep
Research projects
Clinical case studies
You don’t need coding skills or Excel. Just open the tool, enter your values, and you’re done.
Why This Tool Is Useful
If you’re a pharmacy or pharmacology student, this tool will help you understand drug safety better. It removes the confusion of manual formulas and lets you focus on the result.
It’s perfect for:
Lab work
Homework
Exam prep
Research projects
Clinical case studies
You don’t need coding skills or Excel. Just open the tool, enter your values, and you’re done.
How It Helps Learning
By using this tool, you get both a number and a visual aid. The bar graph shows you the gap between ED50 and LD50. The badge tells you if the drug is safe.
This way, you learn not only how to calculate the TI, but also how to interpret it correctly. It supports your understanding of drug development, dosing safety, and clinical risk.
100% Free and Always Online
This calculator is completely free. You don’t need to sign up or download anything. Just visit PharmacyFreak.com, open the tool, and start using it.
It’s always available—on mobile, tablet, or desktop. We built it for pharmacy students like you.