A deckle is a removable wooden frame or "fence" used in manual papermaking. The deckle is placed into a mould to keep the paper pulp slurry within the bounds of the wire facing on a mould, and to control the size of the sheet produced. The mould and deckle is dipped into a vat of water and paper pulp that has been beat (fibrillated). The pulp is quickly scooped out of the vat and the mould and deckle is shaken as excess water is drained off. The deckle is then removed and the newly formed sheet is "couched" (set) onto felts. Fiber that has been beat longer generally requires more time to drain. If the paper slurry gets under, or if long fibers settles on top of the deckle, it will cause a more irregular edge.^{: 119, 177–178}

Beginning in the early 1800s with the invention of the Fourdrinier machine, paper was produced in long rolls and the deckle became mostly obsolete.