Foundation double crochet creates a flexible-looking starting strip with the height of double crochet already attached. It can save you from making a long chain and discovering, one row later, that the width is wrong. The technique becomes much easier when you pause between making the base chain and completing the tall stitch.
Stitch terminology: This guide uses US names. US single crochet is UK double crochet; US half double is UK half treble; US double is UK treble. See the full US/UK reference.
Start with a small strip
Use smooth yarn and a hook that moves easily through it. For this teaching version, begin with four chains. Yarn over, insert into the fourth chain from the hook and draw up a loop. There are now three loops on the hook.
Yarn over and draw through just one loop to form the foundation chain. Complete the double crochet by drawing through two loops, then through the final two. Count this completed foundation double crochet as one; the initial height chains are not an extra stitch in this exercise.
Find the newly made chain
The next stitch begins in the small chain at the bottom of the previous foundation stitch. Yarn over first, insert under two strands of that base chain and draw up a loop. Make another base chain by pulling through one, then complete the two double-crochet pull-throughs.
A marker through the base chain is useful for the first few stitches. If you insert into the top V instead, you will stack stitches upward rather than extend the strip sideways.
Check ten stitches before making a hundred
Make ten foundation double crochets. Count the ten top Vs separately from the base chains. Lay the strip down without stretching it and look at its two long edges. A little movement is normal; a pronounced crescent suggests the chain part and the stitch part have different tension.
For a second practice row, chain two without counting it as a stitch, turn and work ten double crochets. Put the first into the first stitch and the last into the tenth. This explicit edge convention is for the exercise; a published pattern may count its turning chain instead.
Replace the row the pattern actually specifies
If a pattern starts with a plain row of thirty double crochets, thirty foundation double crochets may replace that chain-and-row setup. The foundation strip is already row one. Do not work the original first row again unless you deliberately want extra height.
Take more care with patterns that begin with chain spaces, shaping or stitches worked on both sides of the chain. Their foundation does more than provide a straight line, so a simple one-for-one replacement may change the construction.
Do not mix counts from different tutorials
Some instructions use a different number of setup chains or count the beginning height as a stitch. Follow one convention from start to finish. If the starting end has two apparent tall columns, identify which belongs to the setup before deciding the row is short.
Write the convention beside your sample. A useful note includes the number of completed foundation stitches, the next row’s count and whether the turning chain counts.
Decide from the finished sample
Care for the sample as the yarn label directs, then compare its width and edge stretch with the project requirements. A more yielding edge can be helpful for a scarf or garment, but it does not automatically provide the structure needed for a bag opening. Choose the foundation that suits the fabric’s job.
Continue learning
Practise the shorter foundation · Review double crochet · Keep the repeat count valid
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