TRT Dose Calculator

TRT Calculator: mg/mL Conversion Quick Reference

Testosterone esters come in different concentrations. Here’s how the math works at each concentration for the most common weekly TRT doses:

To convert mL to insulin syringe units: multiply by 100. So 0.5 mL = 50 units on a U-100 insulin syringe. The calculator above does this automatically for any dose and concentration.

How to Use a TRT Calculator for Weekly Dosing

A TRT dosage calculator works the same way whether you inject once a week, twice a week, every 3.5 days, or daily:

• Enter your total weekly dose in mg. Most TRT protocols sit between 100–200 mg/week.
• Enter your testosterone concentration (mg/mL). Check the vial label.
• Pick your injection frequency. More frequent injections mean smaller, more stable shots.
• Read the per-injection volume. This is what you draw into the syringe each time.

Daily microdosing splits the weekly dose across 7 days, which keeps blood levels flatter and tends to reduce side effects from peak/trough swings. The calculator handles this automatically - just select daily injection frequency.

Test E Calculator: Testosterone Enanthate-Specific Dosing

Testosterone enanthate (test E) has an apparent serum half-life of about 6.9 days based on measured pharmacokinetic data (older references sometimes quote ~4.5 days). Even at 6.9 days, a once-weekly injection produces noticeable peak/trough swings for many users, and most TRT patients on enanthate split into two weekly doses (every 3.5 days) for steadier blood levels.

Enanthate is most commonly compounded at 200 mg/mL or 250 mg/mL. For a typical 140 mg/week TRT dose at 200 mg/mL, that’s 0.7 mL once-weekly or 0.35 mL every 3.5 days. The calculator above runs these numbers for any enanthate concentration and frequency you enter.

Cypionate dosing follows the same logic. Both cypionate and enanthate carry the same ~6.9-day apparent serum half-life and are dose-for-dose interchangeable. Propionate is much shorter (~2 days) and typically requires injection every other day.

TRT Calculator FAQ

What is a TRT dose calculator?

A TRT dose calculator converts your weekly testosterone prescription (in mg) into the exact per-injection volume (in mL) based on the concentration of your testosterone preparation. It handles cypionate, enanthate, propionate, sustanon, and other esters at any concentration.

How do I calculate TRT dose in mg/mL?

Divide your per-injection dose by the concentration. Example: 70 mg at 200 mg/mL = 70 ÷ 200 = 0.35 mL per injection. The calculator above does this automatically.

What’s the average TRT dosage per week?

Most TRT protocols sit between 100–200 mg/week of testosterone cypionate or enanthate. Starting doses are typically 100–140 mg/week, with adjustments based on follow-up labs (total testosterone, free testosterone, estradiol, hematocrit).

How does a TRT calculator handle microdosing?

Daily microdosing splits the total weekly dose across seven injections. The calculator divides your weekly mg by 7, then converts that daily mg into mL based on your concentration. Smaller daily volumes typically use a U-100 insulin syringe.

Is this calculator accurate for testosterone enanthate?

Yes. The math is identical for any testosterone ester - cypionate, enanthate, propionate, or sustanon. The only variable that changes is the half-life, which affects injection frequency choice, not the per-injection volume calculation.

TRT Dose Cheat Sheet: Weekly to Daily Conversions

Quick reference for converting your weekly testosterone cypionate dose (200 mg/mL) to daily microdoses in mL and insulin syringe units.

Based on testosterone cypionate at 200 mg/mL concentration. Daily doses are weekly ÷ 7, rounded. Always confirm with your prescriber. See the insulin syringe reading guide if you’re new to measuring units.

How to Calculate Your TRT Injection Dose

Calculating your testosterone injection dose comes down to three numbers: your prescribed dose in milligrams, your vial concentration in mg/mL, and your syringe type.

The formula:

Dose (mL) = Prescribed dose (mg) ÷ Vial concentration (mg/mL)

Example: Your doctor prescribes 140mg of testosterone cypionate per week. Your vial is 200mg/mL.

140 ÷ 200 = 0.7 mL per week

If you inject twice weekly, that’s 0.35 mL per injection. If you use a 1mL insulin syringe (100 units), 0.35 mL = 35 units.

Common Testosterone Concentrations

Most testosterone vials come in one of these concentrations:

Always check your vial label for the exact concentration before calculating your dose. See our testosterone cypionate dosage guide for detailed dosing recommendations by goal and frequency.

Injection Frequency and How It Affects Your Dose

Your total weekly dose stays the same regardless of frequency - you’re just splitting it into smaller, more frequent injections. Here’s how a 140mg/week prescription breaks down:

More frequent injections generally mean more stable testosterone levels. Regimen’s half-life visualizer shows you exactly how your injection frequency affects your estimated blood levels between doses. Learn more about TRT injection schedules and microdosing protocols.

If you log every injection in an app, see our roundup of the best peptide tracker apps for tracking TRT doses, schedules, and bloodwork over time.

How to Read an Insulin Syringe for TRT

Many TRT patients use insulin syringes (especially for daily microdosing or SubQ injections). Here’s how to convert:

• 1 mL insulin syringe = 100 units
• So 0.1 mL = 10 units, 0.2 mL = 20 units, etc.
• At 200mg/mL: 10 units = 20mg of testosterone

For a detailed visual guide with syringe diagrams, see our complete insulin syringe reading guide. For a complete reference table, see: Units vs mL vs mg syringe conversion guide.

Testosterone Cypionate vs Enanthate Dosing

Both esters deliver testosterone with essentially the same apparent serum half-life, so their level curves behave near-identically between injections:

• Testosterone Cypionate: ~6.9-day apparent serum half-life. Most prescribed TRT ester in the US. Available at 100mg/mL and 200mg/mL.
• Testosterone Enanthate: ~6.9-day apparent serum half-life. Most prescribed internationally. Commonly 250mg/mL.

Older references sometimes quote a small gap between the two (~8 days vs ~4.5-7 days), but measured pharmacokinetic data puts them at the same ~6.9 days, and they are dosed interchangeably in practice. Use Regimen’s half-life visualizer to compare the PK curves for each ester at your injection frequency.

For a complete guide to injection scheduling, see our TRT injection schedule guide.

What to Do After Calculating Your Dose

1. Log it in Regimen. Track every injection - dose, volume, injection site, and time with the Regimen app, free for one compound, plus a two-week trial.
2. Visualize your levels. Regimen’s half-life visualizer shows your estimated testosterone levels between injections based on your ester’s half-life.
3. Track your health metrics. Connect Apple Health or Google Health Connect to see how your TRT protocol affects your blood pressure, weight, energy, and sleep over time.
4. Share with your provider. Export your dose history and health data to bring to your next clinic visit.

Download Regimen free - iOS·Android

TRT Dosing in the UK

The UK standard for TRT differs from the US. Sustanon 250 (a blend of four testosterone esters at 250mg/mL) is the NHS default. Nebido (testosterone undecanoate, 1000mg every 10-14 weeks) is common for men preferring less frequent injections. This calculator works for all testosterone esters and concentrations - enter your vial concentration and desired dose to get your exact injection volume.

UK readers: for testosterone ester concentration tables, NHS vs private dosing patterns, and insulin syringe unit conversions specific to UK pharmacy practice, see our TRT dose conversion guide for UK patients.

Data Sources

This tool uses dosing information from official prescribing information:

• Standard TRT Protocols - Testosterone cypionate and enanthate dosing guidelines for hormone replacement therapy
• Oil-Based Injection Standards - Volume calculations for intramuscular and subcutaneous testosterone injections