Statutory guidance

Calculate your fisheries catch limits

How to calculate the live weight of fish based on landed weight and conversion factors.

• From: Marine Management Organisation
• Published: 11 June 2014
• Last updated: 26 February 2024 — See all updates

Documents

Conversion factors

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Details

Catch limits are measured in tonnes (t) or kilograms (kg). They are the maximum live weight that may be caught and retained on board, landed or transhipped, unless otherwise stated.

You calculate the live weight by multiplying landed weight by the appropriate conversion factor.

Published 11 June 2014

Last updated 26 February 2024 + show all updates

1. 26 February 2024

   Conversion factors - update

2. 25 October 2023

   Eastern Atlantic bluefin tuna information added.

3. 7 July 2023

   Updated crabs (claws & legs)

4. 1 May 2018

   Plaice under the Gutted column changed to 1.05

5. 6 February 2018

   Plaice (gutted) changed

6. 11 June 2014

   First published.