Electronics
dB Converter
Switch between gain/loss ratios and decibel measurements using the correct multiplier for power (10 log) or voltage/current (20 log).
Convert between linear power/voltage ratios and decibels (dB/dBm).
Decibel math
Power: dB = 10 log₁₀(P₂/P₁) Voltage: dB = 20 log₁₀(V₂/V₁)
For dB → ratio conversions the equations are inverted: Ratio = 10^{dB/10} for power or 10^{dB/20} for voltage/current.
How to use
- Choose whether you’re converting a ratio to dB or a dB figure back to a ratio.
- Select power or voltage/current mode.
- Enter the known value and copy the converted result.
Example
Input: Mode = Ratio → dB, Type = Voltage, Ratio = 2.5
Output: dB ≈ 7.96
Student-friendly breakdown
This walkthrough emphasizes the most searched ideas for dB Converter: dB Converter. Start with the formula above, then follow the guided steps to double-check your work. For quick revision, highlight the givens, plug into the equation, and finish by verifying your units.
Need more support? Use the links below to open the long-form guide, browse additional examples, or hop into adjacent calculators within the same topic — each one is a quick way to double-check your work or handle a related question without starting from scratch.
Deep dive & study plan
dB Converter: Converts linear power or voltage ratios to decibels and back. It's built around decibels, gain, dbm, so you can go from a raw question to a checked answer without switching tools.
The math behind it: For dB → ratio conversions the equations are inverted: Ratio = 10^{dB/10} for power or 10^{dB/20} for voltage/current. The core relationship is Power: dB = 10 log₁₀(P₂/P₁) Voltage: dB = 20 log₁₀(V₂/V₁), shown above the calculator so you can see exactly how your inputs turn into the result.
To use it well: (1) Choose whether you’re converting a ratio to dB or a dB figure back to a ratio. (2) Select power or voltage/current mode. (3) Enter the known value and copy the converted result. Keep your units consistent as you go, and re-run a case you already know the answer to — it's the fastest way to catch a typo before it throws off a result you're relying on.
Worked example: entering Mode = Ratio → dB, Type = Voltage, Ratio = 2.5 returns dB ≈ 7.96. Try swapping in your own numbers next, especially a case you're unsure about, before you use this for something that matters.
Quick retention checklist
- Speak the formula aloud (or annotate it) so the relationships stick.
- Write each step in your own words and compare with the numbered list above.
- Swap in new numbers for the Example to make sure the calculator (and your logic) handles edge cases.
- Check at least one related calculator below — it's the fastest way to confirm your numbers still line up from a different angle.
FAQ & notes
How do I interpret dBm?
Treat P₁ as 1 mW. The converter shows the ratio so you can derive absolute dBm by comparing P₂ to a 1 mW reference.
Can ratios be less than one?
Yes—ratios below one simply yield a negative decibel value to represent attenuation.
What formula does the dB Converter use?
For dB → ratio conversions the equations are inverted: Ratio = 10^{dB/10} for power or 10^{dB/20} for voltage/current.
How do I use the dB Converter?
Choose whether you’re converting a ratio to dB or a dB figure back to a ratio. Select power or voltage/current mode. Enter the known value and copy the converted result.