Phase Shift Calculator

Calculate the phase shift, period, amplitude, and vertical shift of sine and cosine functions. Supports standard form A·sin(Bx−C)+D and factored form A·sin(B(x−h))+D.

976.4K uses Updated · 2026-05-06 Runs locally · zero upload
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How to Use Phase Shift Calculator

The Phase Shift Calculator extracts the horizontal shift, period, amplitude, and vertical displacement from a trigonometric function definition. Choose the function type (sine or cosine), select the input form, fill in the parameters, and the calculator shows all transformation values instantly.

  1. Choose the function — Select sin or cos.
  2. Choose the input form — Standard form (A·f(Bx − C) + D) or factored form (A·f(B(x − h)) + D).
  3. Enter the parameters — Fill in A, B, C (or h), and D.
  4. Review the results — The Phase Shift Calculator shows the phase shift, its direction (left or right), period, amplitude, and vertical shift.

If B = 0, the function is constant and the phase shift is undefined. The calculator will prompt you to enter a non-zero value for B.

Formula & Theory - Phase Shift Calculator

The Phase Shift Calculator uses this core formula or rule: standard trigonometric transformation formulas:

Standard form:  y = A · sin(Bx − C) + D
                Phase Shift = C / B
                Period      = 2π / |B|
                Amplitude   = |A|

Factored form:  y = A · sin(B(x − h)) + D
                Phase Shift = h
                (Equivalent: C = B·h)
SymbolMeaning
AAmplitude (height from midline to peak)
BFrequency factor (affects period)
CPhase constant in standard form
hHorizontal shift in factored form
DVertical shift (midline)

The sign of the phase shift determines the direction: if C/B > 0, the graph moves right by C/B units; if C/B < 0, it moves left by |C/B| units. This is because the zero-crossing or peak of the function moves in the positive x direction when C is positive.

Assumptions and Limits

B must be non-zero. The amplitude is always taken as a positive value |A|; a negative A reflects the graph vertically. This calculator handles real-number inputs only.

Use Cases for Phase Shift Calculator

The Phase Shift Calculator is particularly useful in:

  • Trigonometry courses — Identify all four transformation parameters from a function equation quickly.
  • Graphing functions — Determine exactly where the first peak, trough, and zero occur on a shifted graph.
  • Physics and engineering — Analyze phase differences between waves in AC circuits, sound waves, or oscillations.
  • Homework and exam preparation — Verify the phase shift calculation before sketching the graph.
  • Comparing two functions — Assess the phase difference between y = sin(2x − π) and y = sin(2x + π/2).

The Phase Shift Calculator eliminates the arithmetic step of dividing C by B and clearly labels the shift direction, which is a common source of sign errors in student work.

Frequently asked questions about Phase Shift Calculator

What is a phase shift in trigonometry?

A phase shift is a horizontal translation of a trigonometric graph. For y = A·sin(Bx − C) + D, the phase shift equals C/B. A positive result means the graph shifts right; a negative result means it shifts left.

How do I find the phase shift from y = A·sin(Bx − C) + D?

Divide C by B. The phase shift = C/B. If B = 2 and C = π, the phase shift = π/2 (shifted right by π/2 units).

What is the difference between the standard and factored forms?

Standard form is y = A·f(Bx − C) + D. Factored form is y = A·f(B(x − h)) + D. In factored form, h directly equals the phase shift. To convert: C = B·h.

Is my data stored?

No. All calculations happen in your browser; nothing is sent to a server.