The Transistor Amplifier Calculator

·Design ·Learn ·Prototype ·Instantly

Explore single-stage and chained BJT amplifiers – right from your browser.

👉 Try it now: ufelectronics.eu/bjt_amp_calculator

What’s This Tool About?

If you’re learning analog electronics, teaching transistor circuits, or prototyping small-signal amplifiers – this tool is built for you.

The Transistor Amplifier Calculator simplifies the design and exploration of BJT amplifier stages (CE, CC, Class AB).

It helps you

• test ideas,
• understand behavior, and
• chain multiple stages together

without writing a single formula or touching a soldering iron.

Why You’ll Find It Useful

🧠 Understand Instantly

Change a value – see the results. This tool bridges the gap between circuit theory and real-world behavior.

Learn how biasing, gain, impedance, and swing interact – and see the effects immediately.

• “What happens if I bypass the emitter resistor?”
• “How does the input impedance affect the next stage?”

Now you don’t just read the answer – you see it.

🛠️ Design Smarter & Faster

• Skip hand calculations and datasheet digging
• Visualize gain, clipping, and output swing
• Explore multiple transistor models and real resistor values

Whether you’re designing a mic preamp or tuning a sensor front-end – you’ll get meaningful output in seconds.

🔗 Build Intuition for Amplifier Chains

Unlike most tools, this calculator supports multi-stage design.

It shows how one amplifier stage affects the next – perfect for system-level understanding:

• Input/output impedance matching
• Gain accumulation
• Signal swing limits & clipping points

Who’s This Tool For?

🎓 Learners

Students, hobbyists, or self-taught makers exploring analog electronics.

✅ “Try different biasing methods and instantly see what works.”

🧑‍🏫 Teachers & Educators

Use it for live demos, online learning, or lab replacements.

✅ “Assign students to build a 3-stage amplifier chain with specific goals.”

⚙️ Engineers & Designers

For rapid analog prototyping and sanity-checking designs.

✅ “What if I drive a Class AB from a common-emitter buffer?”

Key Features at a Glance

• ✔️ Common emitter, collector, and Class AB support
• ✔️ Chain multiple amplifier stages
• ✔️ Realistic BJT models (2N3904, 2N2222, BC547, etc.)
• ✔️ Standard resistor series (E12, E24, E96) with auto-matching
• ✔️ Automatic calculation of gain, Zin, Zout, swing, and component values
• ✔️ Interactive graphs & schematic previews
• ✔️ Export to JSON, CSV, PNG, XML, or clipboard
• ✔️ No install, no login – works on desktop and mobile browser
• ✔️ Dark/light mode toggle

Feedback and Suggestions

This tool is actively developed and shaped by its users.

If you find bugs, have suggestions, or just want to say hi – please reach out via:

• Discord Channel
• YouTube Demo – YouTube comments
• The contact form at ufelectronics.eu

Built By Passion

Created by Andreas Dyhrberg (alias André Dyrberg), a lifelong electronics enthusiast and developer who wanted a smarter, faster way to explore analog circuits.

This is a personal initiative – not a commercial product. It’s free, ad-free, and meant to empower learning.

See It in Action

🔗 Start experimenting now – and discover the analog chain reaction.
👉 Click on this link: ufelectronics.eu/bjt_amp_calculator