# Pascals to Psi (Pa to psi)

> Convert pascals to psi: 1 Pa = 0.000145038 psi. Exact conversion factor, formula, 22-row table and worked examples, with JSON API and MCP access.

- Page id: `pa-to-psi` · Quantity: Pressure (`pressure`, base unit Pa) · Tool: `convert_units`
- Canonical page: https://tttkmbb.com/conversion/pa-to-psi · This document: https://tttkmbb.com/conversion/pa-to-psi.md · JSON: https://tttkmbb.com/conversion/pa-to-psi.json (add `?value=` for a result)

## Formula

- `1 Pa = 0.000145038 psi`
- `psi = pascals × 0.0001450377377`
- Reverse: `pascals = psi × 6894.757293`

The factor follows from the SI definitions of both units (NIST SP 811); values below are rounded to 6 significant figures, the API returns up to 12.

## Worked examples

- 5 Pa = 0.000725189 psi
- 12.5 Pa = 0.00181297 psi
- 100 Pa = 0.0145038 psi

## Conversion table

| Pascals (Pa) | Psi (psi) |
| --- | --- |
| 1 | 0.000145038 |
| 2 | 0.000290075 |
| 3 | 0.000435113 |
| 4 | 0.000580151 |
| 5 | 0.000725189 |
| 6 | 0.000870226 |
| 7 | 0.00101526 |
| 8 | 0.0011603 |
| 9 | 0.00130534 |
| 10 | 0.00145038 |
| 15 | 0.00217557 |
| 20 | 0.00290075 |
| 25 | 0.00362594 |
| 30 | 0.00435113 |
| 40 | 0.00580151 |
| 50 | 0.00725189 |
| 75 | 0.0108778 |
| 100 | 0.0145038 |
| 200 | 0.0290075 |
| 250 | 0.0362594 |
| 500 | 0.0725189 |
| 1000 | 0.145038 |

## API

- `GET https://tttkmbb.com/api/v1/convert?value=5&from_unit=Pa&to_unit=psi` → unified JSON envelope with `result.values.result`, `formula`, `factor`, `sources`, `freshness`
- MCP: server `https://tttkmbb.com/mcp`, tool `convert_units` with `{"value":5,"from_unit":"Pa","to_unit":"psi"}`
- All pressure units: https://tttkmbb.com/api/v1/units?quantity=pressure · full converter: [Pressure Converter](https://tttkmbb.com/conversion/pressure.md)
- Authentication: none. Freshness: `static` (fixed conversion factors).

## FAQ

**How many psi are in one pascal?**

1 Pa = 0.000145038 psi. The factor comes from the SI definitions of both units (NIST SP 811 / BIPM), so it is exact or correct to at least 10 significant figures.

**What is the formula to convert pascals to psi?**

Multiply the value in pascals by 0.0001450377377: psi = pascals × 0.0001450377377. For example, 5 Pa = 0.000725189 psi.

**How do I convert psi back to pascals?**

Multiply by the inverse factor 6894.757293 (pascals = psi × 6894.757293), or use the psi-to-pascals page.

## Related conversions

- [Psi to pascals](https://tttkmbb.com/conversion/psi-to-pa.md) (reverse)
- [Psi to Bar](https://tttkmbb.com/conversion/psi-to-bar.md)
- [Bar to Psi](https://tttkmbb.com/conversion/bar-to-psi.md)
- [Psi to Kilopascals](https://tttkmbb.com/conversion/psi-to-kpa.md)
- [Kilopascals to Psi](https://tttkmbb.com/conversion/kpa-to-psi.md)
- [Bar to Kilopascals](https://tttkmbb.com/conversion/bar-to-kpa.md)
- [Kilopascals to Bar](https://tttkmbb.com/conversion/kpa-to-bar.md)
- [Atmospheres to Pascals](https://tttkmbb.com/conversion/atm-to-pa.md)
- [Pascals to Atmospheres](https://tttkmbb.com/conversion/pa-to-atm.md)

## Data Sources

- NIST Special Publication 811 – Guide for the Use of the International System of Units (SI), Appendix B conversion factors — https://www.nist.gov/pml/special-publication-811 (standard, retrieved 2026-09-24)
- BIPM – The International System of Units (SI Brochure, 9th edition) — https://www.bipm.org/en/publications/si-brochure (standard, retrieved 2026-09-24)
- Wikipedia – Conversion of units — https://en.wikipedia.org/wiki/Conversion_of_units (reference, retrieved 2026-09-24)