# NPK Nutrient Content Calculator

Read N, P₂O₅ and K₂O amounts from a fertilizer label.

[Open this tool](https://whatson.pk/gardening-npk-calculator/)

Category: Gardening

Fertilizer labels commonly state nitrogen alongside phosphorus and potassium oxide conventions.

Enter product mass and the labelled percentages. Read the nutrient amounts and elemental conversions on their stated basis.

## Inputs and controls

* Product mass (kg). Allowed range: 0 to 1000000
* Label N (%). Allowed range: 0 to 100
* Label P₂O₅ (%). Allowed range: 0 to 100
* Label K₂O (%). Allowed range: 0 to 100

## How to use

* Enter product mass.

* Enter label N, label P₂O₅ and label K₂O.

* Select Calculate result. Read the returned values alongside the assumptions below before copying, exporting or acting on the result.


## Why use this tool

Separate label and elemental figures help prevent comparisons between unlike nutrient units.


## Before relying on the result

P₂O₅ and K₂O are label conventions, not elemental P and K. Conversion factors are also shown; this does not check crop sufficiency.


## Tool limitations

P₂O₅ and K₂O are label conventions, not elemental P and K. Conversion factors are also shown; this does not check crop sufficiency.

## Questions

### Is P2O5 the same as elemental phosphorus?

No. They use different mass conventions. Use the displayed conversion and keep the nutrient basis consistent.

### What should I check before using NPK Nutrient Content Calculator?

Check Product mass, Label N, Label P₂O₅ and Label K₂O. Use the exact units shown beside the controls and replace any example values with your own inputs.

Source page last modified (UTC): 2026-10-04T13:08:12+00:00

This profile describes the tool. It does not execute it or supply a professional certification.