Teaspoons to Milliliters Converter

Clinical Pharmacology & Culinary Teaspoon Metrology (USP & AAP)

The teaspoon (tsp) has two primary modern definitions:

• **

• Metric / Medical Dosing Teaspoon (USP Standard)**:

1 Metric / Medical tsp 5.0000 mL Exact = (1) / (3) Metric tbsp

Milliliters (mL) = Teaspoons × 5.0000, Teaspoons (tsp) = mL5.0000

• **

• US Customary Culinary Teaspoon (NIST Handbook 44)**:

1 US tsp (1) / (6) US fl oz = 4.928922 mL = (1) / (3) US tbsp

• **

• Standard Clinical & Kitchen Benchmarks**:

• 0.5 tsp (Medical) = 2.5000 mL = 50 drops (gtt)

• 1.0 tsp (Medical) = 5.0000 mL = 100 drops

• 2.0 tsp (Medical) = 10.0000 mL

• 3.0 tsp (1 Tablespoon) = 15.0000 mL

• 1.0 US Customary tsp (Baking) = 4.9289 mL = 0.1667 fl oz

How to Use This Calculator

Enter your Volume Value to Convert (e.g. 1), Teaspoon Standard & Clinical System — choose from Metric & Clinical Medical Teaspoon (5.00 mL Exact - Oral Syringes & Liquid Medicine), US Customary Teaspoon (4.93 mL = 1/6 US fl oz = 1/3 tbsp - Baking Recipes), UK Imperial Teaspoon (5.92 mL = 0.208 Imp fl oz - Historical British), Conversion Direction — choose from Teaspoons (tsp) to Milliliters (mL = tsp × ml_per_tsp), Milliliters (mL) to Teaspoons (tsp = mL ÷ ml_per_tsp), and Pediatric & Culinary Benchmark — choose from Custom Volume Value, 1.0 Metric / Medical tsp (Oral Dosing Syringe) → 5.0000 mL Exact (0.333 tbsp), 1.0 US Customary tsp (Baking Recipe) → 4.9289 mL (0.1667 fl oz). Results update instantly as you type — adjust any value to compare scenarios.

The Formula

Formula Reference: Teaspoons to Milliliters Converter

Input variables:

volumeQuantityInput — Volume Value to Convert

teaspoonSystemSelect — Teaspoon Standard & Clinical System

conversionDirectionSelect — Conversion Direction

Computed outputs:

convertedPrimaryResult — Converted Primary Output

tablespoonsEquivalent — Tablespoons (tbsp)

fluidOuncesEquivalent — US Fluid Ounces (fl oz)

medicalDropsEquivalent — Standard Drops (gtt - 20 drops/mL)

litersEquivalent — Liters (L)

Mathematical relationships extracted from calculation logic:

mlPerTsp = 5.0; // Metric & Medical standard

mL = tsp * mlPerTsp

tbsp = tsp / 3.0

flOz = mL / 29.5735295625

drops = mL * 20.0; // 20 drops per mL standard IV/medical

liters = mL / 1000.0

Reference constants:

mlPerTsp = 5.0

Standard: NIST Handbook 44 and BIPM SI unit definitions

Worked Example

A parent administering a 10.0 mL liquid amoxicillin antibiotic dose to a child converts it to medical teaspoons as 10.0 ÷ 5.0 = 2.0000 teaspoons for oral syringe verification.

Understanding Your Result

Unit conversion precision: round to the same number of significant figures as your original measurement. Converting 6 feet to meters gives 1.8288 m — but if your measurement was approximate (±1 inch), expressing more than 2 decimal places is false precision. For international trade and technical specifications, SI units (meters, kilograms, liters) are the standard. US customary units (feet, pounds, gallons) differ from Imperial UK units: 1 US gallon = 3.785 L vs. 1 UK gallon = 4.546 L.