Filet crochet builds a picture from open and filled mesh cells. A chart square represents a cell in that mesh, not necessarily one crochet stitch. Once you understand how neighbouring cells share their boundary stitches, the counting becomes much less mysterious.
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.
Check which mesh system the pattern uses
A common system uses a double-crochet boundary, two chain positions and the next double-crochet boundary for an open cell. A filled cell replaces the chain positions with double crochets. Other filet systems use different spacing, so begin with the designer’s key.
In the common three-position-per-cell system, adjacent cells share the boundary double crochet. Five cells need 3 × 5 + 1 = 16 stitch positions across the row. They do not need twenty separate double-crochet boundaries.
Build a simple five-cell practice row
Start with a base row of sixteen single crochets, made from seventeen chains. For the mesh row, chain three and count it as the first double crochet. Skip its base stitch, chain two, skip the next two base stitches and double crochet in the next. Repeat that chain-two, skip-two, double-crochet sequence five times in total.
You now have five open cells. The row contains six double-crochet boundaries, including the starting chain-three, and ten chains between them: sixteen positions altogether.
Understand a filled cell
To fill a cell, work double crochets in the two positions that would otherwise be chains, then complete the next boundary double crochet. The boundary already made on the previous cell is shared.
| Five-cell row | Double-crochet positions | Chain positions | Total |
|---|---|---|---|
| All open | 6 | 10 | 16 |
| All filled | 16 | 0 | 16 |
A mixed row still occupies sixteen positions. The picture changes because some positions are solid and others open, not because the width gains or loses stitches every time a square is filled.
Follow the route through the chart
Mark the row number and reading direction. Turned rows usually alternate direction. If you are making lettering, identify the intended display side before you begin; reading every row from the same edge can reverse or scramble the design.
For the first sample, use a simple arrangement such as one filled central cell with open cells on either side. Count cells separately from individual stitch tops.
Measure whether the cells are square
A drawn square does not guarantee a square cell in the fabric. Your double-crochet height and chain-space width determine the proportions. Make several cells in both directions, finish the sample according to the yarn label and measure the resulting grid.
If a circular picture looks stretched, the issue may be cell proportions rather than a chart-reading error. Adjust the sample method before making a large panel, while preserving the pattern’s stitch structure.
Choose a finish that preserves the openwork
Plan where tails will be hidden, especially around open cells where a bulky join can be visible. A border can frame the design, but it cannot correct a missing boundary stitch in the middle.
Keep the chart key, mesh formula and measured cell size with the project. Those three details are essential if you later resize the design or substitute yarn.
Continue learning
Check the repeat formula · Follow chart symbols · Practise the boundary stitch
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