Linear Interpolation
Linear interpolation estimates a value on the straight line through two known points. It is useful when a small interval can reasonably be treated as linear.
Linear Interpolation
Algebra · 5 inputs
How to use this calculator
- Enter start x in units.
- Enter start y in units.
- Enter end x in units.
- Enter end y in units.
- Enter target x in units.
- Select Calculate and keep the output unit with the answer.
Before you use the answer
Choose the reference quantity before interpreting the number. A ratio, a percentage and a percentage-point difference may use the same observations while answering different questions. For recorded data, keep the original values beside the summary so an unexpected result can be traced back to its inputs.
Equal x coordinates cannot define this function. Outside the endpoints the calculation becomes extrapolation.
Does it save my inputs?
No calculation history is stored by this website. The calculator works locally in your browser. See the privacy policy for hosting and contact details.
Why might a result be approximate?
Measurement uncertainty, ideal-model assumptions and floating-point rounding can all matter. Displaying more digits does not improve the original measurement.
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