555 Timer Calculator

Calculate the timing intervals of a 555 Timer, in astable mode with this professional-grade tool. Perfect for electronics engineers and hobbyists.

Component Values

R1 (Ω)

R2 (Ω)

C (F)

Frequency

0.00 Hz

Duty Cycle 0.00%

How to use

Enter R1, R2, and C values for a 555 timer in astable mode. The calculator outputs frequency and duty cycle.

Frequency is calculated with the standard 555 astable formula, and duty cycle is derived from the resistor ratio.

Calculate the timing intervals of a 555 Timer, in astable mode with this professional-grade tool.

Formulas

\[f = \frac{1.44}{(R1 + 2R2)C}\]
\[D = \frac{R1 + R2}{R1 + 2R2} \times 100\%\]

Citations

Texas Instruments — ti.com · Accessed 2026-01-19
https://www.ti.com/lit/ds/symlink/lm555.pdf

Changelog

0.1.0-draft — 2026-01-19 — Initial audit spec draft generated from HTML extraction (review required). Verify formulas match the calculator engine and convert any text-only formulas to LaTeX. Confirm sources are authoritative and relevant to the calculator methodology.

✓ Verified by Ugo Candido

Last Updated: 2026-01-19

Version 0.1.0-draft