# SGR Calculator — Fish Growth Rate Calculator

> From two sample weighings, calculate the specific growth rate (SGR), daily weight gain and how many days it takes to reach the target weight at this rate.

- URL: https://demo.fcrsoft.com/en/tools/sgr-growth-calculator
- Language: en
- Updated: 2026-10-03
- Publisher: FCRSOFT (https://fcrsoft.com)

[Demos](https://demo.fcrsoft.com/?hl=en) / [Free Tools](https://demo.fcrsoft.com/en/tools) / SGR and Growth Rate Calculator Free tool

# SGR and Growth Rate Calculator

Enter the average weights from two sample weighings and the number of days between them.
[See the system that does this automatically Open the live demo](https://demo.fcrsoft.com/login.php?package=farm)

## Calculator

First average weight : 120 g
Latest average weight : 165 g
Days between : 30 days
Target weight : 400 g

This calculator runs in your browser; the data you enter is not stored.

## Results

SGR (% per day)
1.06
%

Daily weight gain
1.50
g

Weight gain over the period
37.5 %

Days to target weight
83
days

**Plan Growth and Harvest Automatically**At this rate you reach the target weight in **83** days. FCRSOFT builds the growth curve and harvest forecast from every sample weighing automatically.
[Open the live demo](https://demo.fcrsoft.com/login.php?package=farm) [Fish Production Tracking Software](https://demo.fcrsoft.com/en/solutions/fish-production-tracking-software)

## How is it calculated?

- SGR (%/day) = (ln Final weight − ln Initial weight) ÷ Days × 100

- Daily gain = (Final weight − Initial weight) ÷ Days

- Days left = ln(Target ÷ Latest weight) ÷ (SGR ÷ 100)

FCRSOFT

## FCRSOFT does this for you automatically

You don’t need to do the calculations and checks on this page by hand every day. FCRSOFT derives them all automatically from the records entered in the field.

- Every sample weighing yields a growth curve and SGR.

- The harvest date forecast for the target weight updates automatically.

- Mortality and harvest exits are deducted from stock automatically.

[Open the live demo](https://demo.fcrsoft.com/login.php?package=farm) [Explore the Farm package](https://demo.fcrsoft.com/demo/farm?hl=en)

[demo.fcrsoft.com](https://demo.fcrsoft.com/login.php?package=farm)

## Related tools and guides

[Guide ### What Is SGR (Specific Growth Rate)? What is SGR (specific growth rate), how is it calculated and interpreted? Daily weight gain, TGC and using SGR to forecast harvest. Read the guide](https://demo.fcrsoft.com/en/aquaculture/what-is-sgr) [Free tool ### Harvest Date and Quantity Calculator From current weight, target harvest weight and growth rate, calculate the estimated harvest date, harvest quantity and the feed needed until harvest. Open the tool](https://demo.fcrsoft.com/en/tools/harvest-date-calculator) [Free tool ### Fish Biomass Calculator Calculate total biomass from fish count and average weight, the remaining fish after survival, and cage/pond stocking density (kg/m³). Open the tool](https://demo.fcrsoft.com/en/tools/fish-biomass-calculator) [Free tool ### FCR Calculator Free FCR calculator: instantly work out economic and biological FCR, feed cost per kg and the savings from a 0.1 FCR improvement, from biomass gain and feed given. Open the tool](https://demo.fcrsoft.com/en/tools/fcr-calculator)