If you've ever finished a gorgeous handmade card only to realize it doesn't fit any envelope you own, welcome to the club. I did this three times before I finally sat down and figured out which card sizes actually matter.
Standard card sizes at a glance
There are really only four card sizes you need to know. Everything else is a variation. The A2 (4.25 x 5.5 inches) is the most common handmade card size, and it's what I use for about 80% of my projects. It fits a standard A2 envelope, which you can buy in bulk basically anywhere.
Next up is the A6 (4.75 x 6.5 inches), which is slightly larger and great for photo cards or when you need more real estate for a detailed design. The A7 (5 x 7 inches) is the big one — invitation territory. And then there's the mini card (3 x 3 or 3.5 x 5), perfect for gift tags or quick thank-you notes.
Card to envelope pairing chart
This is where people get tripped up. The envelope should be about 0.25 inches larger than the card on each side. Here's every pairing I use regularly:
A1 card (3.5 x 4.875 inches) goes in an A1 envelope (3.625 x 5.125 inches). A2 card (4.25 x 5.5 inches) goes in an A2 envelope (4.375 x 5.75 inches) — this is the one you'll use the most. A6 card (4.75 x 6.5 inches) matches an A6 envelope of the same dimensions. A7 card (5 x 7 inches) needs an A7 envelope (5.25 x 7.25 inches). And for square cards at 5.5 inches, you'll need a 5.75 x 5.75 envelope.
If you're mailing, add an extra 0.125 inches for breathing room — nobody wants to fight a card into an envelope. And heads up: square envelopes require extra postage with USPS. I learned this the hard way when my holiday cards cost an extra $0.30 each to mail.
Which size should you use?
Here's my honest take after making hundreds of cards: start with A2. Buy a pack of 100 A2 cards and envelopes from your craft store. Learn on that size. Get comfortable. Then branch out when you have a reason to — like a wedding invitation that needs the A7 grandeur, or a tiny gift tag situation.
I wasted money early on buying five different card sizes "just in case." Most of them are still in my craft closet, untouched. Your Silhouette or Cricut can cut any size anyway — the constraint is always the envelope, not the card.
Card sizes and your cutting machine
If you're using a Cricut Joy, you're limited to 4.5 inches wide on the card mat. That means A2 cards are your sweet spot. The Joy's dedicated card mat is actually brilliant — you insert your pre-scored cardstock, and the machine cuts the design on the front panel only. But you're locked into that A2 format.
The Cricut Maker and Explore Air 2 can handle anything up to 11.5 inches wide on a standard grip mat, so all card sizes work fine. The Silhouette Cameo handles up to 12 inches wide as well. With either of these machines, card size is never the limitation — your imagination and your envelope supply are.
One tip I wish someone had told me: when setting up your card in Silhouette Studio or Design Space, always double your width for the fold. An A2 card is 4.25 x 5.5 inches when folded, but you need to cut an 8.5 x 5.5 inch piece and score down the middle. Sounds obvious, but I've seen people cut the folded size and end up with a card half the intended size. That person was me. Twice.
The best card size for each occasion
After ten years and probably a thousand cards, here's what I've settled on for different occasions:
Birthday cards: A2, every time. Classic proportions, fits standard designs, and everyone has A2 envelopes on hand. I can stamp a sentiment, add a quick die-cut, and have a finished birthday card in under 10 minutes.
Wedding invitations: A7. The extra size communicates formality. You've got room for calligraphy fonts, decorative borders, RSVP details, and whatever embellishment makes the couple happy. A2 wedding invitations exist, but they always feel like they're trying too hard to be casual.
Holiday photo cards: A6 or 5x7. You need room for the photo plus a border plus your message. An A2 is too tight for photo cards unless the photo IS the entire card. I use 5x7 for our family Christmas card every year — it's just the right amount of real estate.
Thank-you notes: A2 or mini. Nobody writes a thank-you novel. Keep it small, keep it sincere, keep it quick.
Gift tags: 2 x 3.5 inches or 3 x 3 inches. Punch a hole in the corner, thread some baker's twine, done. I cut these 12 at a time from a single sheet of cardstock and keep a stash in my wrapping supply drawer.
My go-to card stock weights
For the card base, I use 80lb or 100lb cardstock. Anything lighter flops around; anything heavier is hard to fold cleanly without scoring first. And even with scoring, cardstock above 120lb tends to crack at the fold, especially on larger cards like A7.
For layered elements on top of the card, 65lb works great — thick enough to hold shape but not so thick it creates a bulky stack when you've got three or four layers going. For die-cut sentiment strips and tiny details, I sometimes drop to 50lb or even regular printer paper — at that scale, stiffness doesn't matter.
White and cream are your workhorses. Buy those in bulk. Buy colors in single sheets until you know what you actually use — I have a drawer full of chartreuse cardstock that seemed like a great idea in 2014. Still haven't touched it.
Card making supplies checklist for beginners
You don't need much to start making cards. Seriously. Here's my "if you buy nothing else" list:
A pack of 100 A2 pre-scored cards and envelopes (about $12-15). A basic paper trimmer (I've used a Fiskars for years — it's under $20 and works perfectly). Double-sided tape or a tape runner for adhesive. One ink pad in a neutral color (I'd say black Memento or Versafine). One clear stamp set with sentiments. And if you're feeling fancy, a set of colored markers or pencils for adding color to stamped images.
That's it. That's the starter kit. Everything else — cutting machines, die-cut sets, embossing folders, specialty papers — is gravy. Fun gravy, but gravy. I made my first 50 cards with nothing but scissors, a ruler, cardstock, and rubber stamps. They weren't gorgeous, but people loved them anyway because they were handmade.
USPS mailing requirements for handmade cards
If you're mailing your cards, the post office has opinions. Strong opinions. Here are the requirements that matter for card makers:
Minimum size is 3.5 x 5 inches. Maximum for standard letter postage is 6.125 x 11.5 inches. Maximum thickness is 0.25 inches (about 6mm). If your card has bulky embellishments — ribbon, buttons, chipboard pieces, dimensional stickers — it might exceed this and get kicked to the "non-machinable" surcharge.
Square cards cost extra. USPS charges a non-machinable surcharge (currently $0.30) for square envelopes because their sorting machines can't handle them. Beautiful? Yes. Expensive to mail in bulk? Also yes.
Rigid cards cost extra too. If it doesn't bend, the sorting machines can't process it, and you'll pay more. So if you've mounted your card on chipboard or used thick foam adhesive, expect the surcharge.
My advice: make your holiday cards A2, skip the square envelope trend, and keep embellishments relatively flat. Your wallet will thank you when you're mailing 60 cards in December.