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Linear Interpolation Calculator

Math Calculators

Interpolate or extrapolate between two points, table lookup

Quick Answer

Linear Interpolation Calculator: Interpolate or extrapolate between two points, table lookup. Linear Interpolation Calculator uses standard math formulas to compute accurate results instantly.

Known points

Interpolated y_q

996.9

Within [x₀, x₁] — interpolation

Slope k-0.26
ModeInterpolation

Steps

  1. 1斜率 k = (y₁ − y₀) ÷ (x₁ − x₀) = (995.6 − 998.2) ÷ (30 − 20) = -0.26
  2. 2y_q = y₀ + (x_q − x₀) × k = 998.2 + (25 − 20) × -0.26
  3. 3y_q = 996.9
  • Formula: y_q = y₀ + (x_q − x₀) × (y₁ − y₀) ÷ (x₁ − x₀) — assumes the two points are joined by a straight line.
  • Typical uses: reading values between table entries (density, viscosity, steam tables), sensor calibration curves, exam grade boundaries.
  • Extrapolation (x_q outside [x₀, x₁]) assumes the trend continues — real data often bends, so verify before trusting.
  • For multiple segments, apply the formula pairwise to the bracketing points of x_q.

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How to Use

  1. Enter values or expressions: type directly into the Linear Interpolation Calculator — keyboard friendly.
  2. Instant results: everything computes live as you type, no button needed.
  3. Follow the steps: the result panel shows full working and formula substitution.
  4. Copy or recompute: one-click copy; change any input to recalculate instantly.

Key Points

  • Linear Interpolation Calculator is a free online math tool — open and use, no sign-up.
  • All calculations run locally in your browser; your data never leaves the device.
  • Key capability: Interpolate or extrapolate between two points, table lookup.
  • Results come with formulas and reference tables so you can verify every number.

Formula & How It Works

Linear Interpolation Calculator formula

Linear Interpolation Calculator uses standard math formulas to compute accurate results instantly.

FAQ

How do I use the Linear Interpolation Calculator?
Open the page and fill in the input fields — results update automatically. Interpolate or extrapolate between two points, table lookup.
Are the results accurate?
Yes. All calculations use standard mathematical formulas and are verified for accuracy.
Is it free? Do I need to sign up?
Completely free. No registration, login or download required — just open and use.
Does it work on mobile?
Yes. The responsive design works on phones, tablets and desktops.
Is my data saved?
No. All calculations run locally in your browser. Nothing is uploaded or stored.

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Source & Updates

Standard mathematical formulas. All logic verified. Last updated: 2025-07

Last updated:

Formulas and content on this page are reviewed by the YiJianSuan team. For reference only — official sources prevail.

Maintained and periodically reviewed by the YiJianSuan editorial team — review process in ourEditorial Policy.

Cite this page: YiJianSuan. Linear Interpolation Calculator[EB/OL]. https://www.yijiansuan.com/en/c/math/linear-interpolation

Results provided by this tool are for reference only and do not constitute professional advice.