Here is an (incomplete) list of quilts that you can make with 21 Fat Quarters! If you click on the link, it will take you to the page where you can purchase and/or download the pattern:
- Framed Folk Quilt by Modernly Morgan (Twin)
- Finished size: 77" x 90"
- Background Fabric and sashing: 4 yard
- Binding Fabric and sashing squares: 3/4 yard
- Backing Fabric: 5.5 yards

Photo by @modernlymorgan
- Mod Mountains by Suzy Quilts (Queen)
- Finished size: 91" x 104"
- Background Fabric: 7 3/4 yard
- Binding Fabric: 3/4 yard
- Backing: 8 1/4 yards

Photo by @suzyquilts
- Quilty Stars by Quilty Love (King)
- Finished size: 107" x 107"
- Background Fabric: 7 5/8 yards
- Binding Fabric: 7/8 yards
- Backing Fabric: 9 5/8 yards

Photo by @emily_dennis_
- Compass Star Quilt by Quilty Love (Queen size)
- Finished size: 92" x 106"
- Background Fabric: 6 5/8 yards
- Binding Fabric: 1 yard
- Backing Fabric: 8 1/3 yard

Photo credit:
@emily_dennis_