International
C6
114 × 162 mm · 4.488 × 6.378 in
3 × 8 mmtotal unused width × height
View reference →Supporting matcher
Find an envelope for a finished insert
Enter the flat or already-folded size. Results are separated into recommended, borderline and does-not-fit groups, with rotation and exact clearance shown.
Dimensional guidance
16 recommended fits and no borderline possibilities
“Remaining” means total unused width × height after the selected per-edge clearance—not space per edge.
Recommended fit
Both final remaining dimensions are at least 2 mm.
US announcement
A6 announcement
4 3/4 × 6 1/2 in · 120.65 × 165.1 mm
9.65 × 11.1 mmtotal unused width × height
View reference →US commercial
#11
4 1/2 × 10 3/8 in · 114.3 × 263.52 mm
3.3 × 109.52 mmtotal unused width × height
View family guide →US square
6 1/2 × 6 1/2 square
6 1/2 × 6 1/2 in · 165.1 × 165.1 mm
54.1 × 11.1 mmtotal unused width × height
View family guide →US announcement
A7 invitation
5 1/4 × 7 1/4 in · 133.35 × 184.15 mm
22.35 × 30.15 mmtotal unused width × height
View reference →US commercial
#12
4 3/4 × 11 in · 120.65 × 279.4 mm
9.65 × 125.4 mmtotal unused width × height
View family guide →US square
7 × 7 square
7 × 7 in · 177.8 × 177.8 mm
66.8 × 23.8 mmtotal unused width × height
View family guide →US commercial
#14
5 × 11 1/2 in · 127 × 292.1 mm
16 × 138.1 mmtotal unused width × height
View family guide →US announcement
A9 announcement
5 3/4 × 8 3/4 in · 146.05 × 222.25 mm
35.05 × 68.25 mmtotal unused width × height
View family guide →International
C5
162 × 229 mm · 6.378 × 9.016 in
51 × 75 mmtotal unused width × height
View reference →US booklet
9 × 12 booklet
9 × 12 in · 228.6 × 304.8 mm
117.6 × 150.8 mmtotal unused width × height
View family guide →US catalog
9 × 12 catalog
9 × 12 in · 228.6 × 304.8 mm
117.6 × 150.8 mmtotal unused width × height
View family guide →International
C4
229 × 324 mm · 9.016 × 12.756 in
118 × 170 mmtotal unused width × height
View reference →US booklet
10 × 13 booklet
10 × 13 in · 254 × 330.2 mm
143 × 176.2 mmtotal unused width × height
View family guide →US catalog
10 × 13 catalog
10 × 13 in · 254 × 330.2 mm
143 × 176.2 mmtotal unused width × height
View family guide →International
C3
324 × 458 mm · 12.756 × 18.031 in
213 × 304 mmtotal unused width × height
View family guide →Does not fit
The six closest failed candidates are shown first.
International
DL
110 × 220 mm · 4.331 × 8.661 in
-1 × 66 mmtotal unused width × height
View reference →US square
6 × 6 square
6 × 6 in · 152.4 × 152.4 mm
41.4 × -1.6 mmtotal unused width × height
View family guide →US commercial
#10
4 1/8 × 9 1/2 in · 104.77 × 241.3 mm
-6.23 × 87.3 mmtotal unused width × height
View reference →US announcement
A2 announcement
4 3/8 × 5 3/4 in · 111.13 × 146.05 mm
0.13 × -7.95 mmtotal unused width × height
View family guide →US commercial
#9
3 7/8 × 8 7/8 in · 98.42 × 225.42 mm
-12.58 × 71.42 mmtotal unused width × height
View reference →US square
5 1/2 × 5 1/2 square
5 1/2 × 5 1/2 in · 139.7 × 139.7 mm
28.7 × -14.3 mmtotal unused width × height
View family guide →Show 4 more failed candidates
US commercial
#6 3/4
3 5/8 × 6 1/2 in · 92.07 × 165.1 mm
-18.93 × 11.1 mmtotal unused width × height
View family guide →US square
5 × 5 square
5 × 5 in · 127 × 127 mm
16 × -27 mmtotal unused width × height
View family guide →US announcement
A1 / 4-bar
3 5/8 × 5 1/8 in · 92.07 × 130.17 mm
-18.93 × -23.83 mmtotal unused width × height
View family guide →International
C7
81 × 114 mm · 3.189 × 4.488 in
-30 × -40 mmtotal unused width × height
View family guide →A calculated fit is not a guarantee.
Envelope dimensions are nominal exterior measurements. Seams, lining, paper thickness, multiple inserts, embellishments and manufacturing tolerances reduce usable space. Sample before a bulk order or print run.
How ranking works
Recommended candidates are ordered by useful closeness: the smallest positive remaining area after clearance appears first. Borderline candidates are listed separately below them, so a technically positive but impractical result never becomes the lead recommendation.
The documented practical buffer
After the chosen clearance has been applied on every edge, a result is borderline when less than 2 mm remains in either final dimension. This is a cautious working rule, not a manufacturing standard.
Privacy and scope
Inputs are calculated in the browser and are not deliberately retained or sent to analytics. The tool does not infer paper thickness, postage, machinability, supplier stock or guaranteed fit.