# ksi to PSI Converter

URL: https://speedycalculator.com/calculators/conversion/ksi-to-psi/
Last updated: 2026-10-25

> Convert ksi (ksi) to psi (psi): 1 kilopound per square inch = 1,000 psi, so multiply by 1,000 or divide by 0.001. Both fields are editable, so you can also type in psi and get ksi back.

## Inputs

- Ksi (ksi)

## Results

- Psi

## Formula

```
1 ksi = 1,000 psi
1 psi = 0.001 ksi
psi = ksi × 1,000
```

## Explanation

One ksi is 1,000 psi. Engineers use ksi to keep strength values short: 60 ksi rebar has a 60,000 psi yield strength.

### How to use the ksi to PSI Converter

- Type the number of ksi into the **Ksi** field. Decimals such as 0.5 are fine.
- Read the answer in **Psi** – it updates as you type, with no button to press.
- To convert the other way, type into **Psi** and the ksi are recalculated.
- Press **Copy results** to copy both values with the page title, or **Copy link** to share this exact conversion.

This page converts only ksi ⇄ psi. Need a different unit? Use the general pressure converter, where you can choose any “from” and “to” unit.

### How it works

Both units measure pressure, so they are always in the same ratio: one kilopound per square inch equals 1,000 psi. The calculator multiplies the number of ksi you type by 1,000 to give psi, and when you type into the psi field it divides by the same factor to give ksi. Because the ratio never changes, doubling the ksi always doubles the psi. Results are calculated at full precision and rounded only for display (up to eight decimal places, with very large or small values shown in scientific notation).

### How to convert ksi to psi

- Write down the value in ksi, for example **1 ksi**.
- Multiply by the conversion factor 1,000 (because 1 kilopound per square inch = 1,000 psi).
- 1 × 1,000 = **1,000 psi**.
- To go back from psi to ksi, divide by 1,000 – or multiply by 0.001.

### ksi to psi conversion table

KsiPsiPsiKsi0.5 ksi500 psi1 psi0.001 ksi1 ksi1,000 psi2 psi0.002 ksi2.5 ksi2,500 psi5 psi0.005 ksi3 ksi3,000 psi10 psi0.01 ksi4 ksi4,000 psi20 psi0.02 ksi5 ksi5,000 psi50 psi0.05 ksi36 ksi36,000 psi100 psi0.1 ksi50 ksi50,000 psi1,000 psi1 ksi60 ksi60,000 psi

### What is a kilopound per square inch?

A ksi is 1,000 psi. U.S. engineers use it for material strengths, such as 36 ksi structural steel or 4 ksi concrete.

### What is a pound per square inch?

Pounds per square inch is the pressure of one pound-force on one square inch, about 6,895 Pa. U.S. tyre gauges, compressors and hydraulic equipment read psi.

### Common mistakes to avoid

Mixing gauge pressure (psig, barg) with absolute pressure (psia, bara), treating bar and atm as identical, and confusing kgf/cm² with bar.

## Worked example

Inputs — Ksi: 1 ksi.

Results — **Psi = 1,000 psi**.

## FAQ

**How many psi in a ksi?**
1,000.

**What is 4 ksi concrete?**
Concrete with 4,000 psi compressive strength.

**How do I convert ksi to psi?**
Multiply the number of ksi by 1,000. For example, 1 ksi × 1,000 = 1,000 psi.

**How do I convert psi back to ksi?**
Divide by 1,000 (or multiply by 0.001), or simply type the value into the psi field above.

**What is 5 ksi in psi?**
5 ksi = 5,000 psi.

**What is 50 ksi in psi?**
50 ksi = 50,000 psi.

**Is this conversion exact?**
Yes. The factor comes from the official definitions of both units (NIST and the SI), so the only difference you may see is rounding in the last displayed digit.

**Can I convert to other units on this page?**
This page converts only between ksi and psi. To pick any pressure unit, use the general pressure converter linked under Related calculators.

**What formula does the ksi to PSI Converter use?**
1 ksi = 1,000 psi.


## Sources

- [NIST Special Publication 811 – Guide for the Use of the International System of Units](https://www.nist.gov/pml/special-publication-811)
- [NIST Handbook 44 Appendix C – General tables of units of measurement](https://www.nist.gov/pml/owm/nist-handbook-44-current-edition)