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\nAt Mug Mellow, “size” means capacity: how much a mug, travel mug, tumbler or kids cup holds. This guide lists every capacity in the shop with its millilitre conversion, explains what each size feels like in everyday use, and helps you choose between two options when a design offers both. It also explains how sizes affect the print, why long names and family lists suit a bigger mug, and what to do if the size you chose turns out to be wrong. If you still cannot decide, email support@mugmellow.shop; we reply within 24 hours on business days.
\nEvery size in the shop is stated in US fluid ounces (fl oz), with an approximate conversion to millilitres. One US fluid ounce is about 29.6 ml, so the conversions below are rounded to the nearest 5 ml. Capacity is measured to the brim, which is more than you would pour in practice: most people leave a finger’s width at the top for milk or for carrying the mug without spilling. A useful rule is that a mug filled comfortably holds roughly 85 to 90 percent of its stated capacity.
\nWe do not list heights, diameters or weights on this page. Product shapes vary between designs, and we only publish numbers we can stand behind. If a particular measurement matters to you, for example whether a tumbler will fit a cup holder or a mug will sit under a coffee machine spout, email us before ordering and tell us the space you have.
\n| Capacity | \nAbout | \nWhere you will find it | \nGood for | \n
|---|---|---|---|
| 8 oz | \n235 ml | \nKids ceramic cocoa mug | \nHot chocolate or milk for a young child, at the table | \n
| 11 oz | \n325 ml | \nCeramic name, photo and two-tone mugs; heat-reveal mug | \nA standard cup of coffee or tea with room for milk | \n
| 12 oz | \n355 ml | \nLatte mug, enamel camp mug, kids straw cup | \nFoamy coffee, a porch coffee, a child’s drink with a lid | \n
| 14 oz | \n415 ml | \nInsulated travel mug with handle, Dad’s coffee travel mug | \nA commute coffee in a mug shape | \n
| 15 oz | \n444 ml | \nCeramic name, photo and two-tone mugs; photo travel mug | \nA bigger pour, long names and family lists | \n
| 16 oz | \n475 ml | \nGlass can, frosted glass mug, slim commuter travel mug, kids push-button bottle | \nIced coffee, cold drinks, one-handed carrying, a school bag | \n
| 20 oz | \n590 ml | \nSkinny name tumbler, pet photo and teacher tumblers, kids handle tumbler | \nWater or iced coffee at a desk, in a car or at school | \n
| 30 oz | \n890 ml | \nPet photo and teacher tumblers | \nLong days out, fewer refills | \n
| 40 oz | \n1,180 ml | \nHandle tumbler with name | \nAll-day water with one refill at lunch | \n
Most ceramic designs come in both sizes, and this is the choice we are asked about most. Here is how we think about it.
\nFor example, a “Nana” mug with six grandchildren’s names reads more comfortably on 15 oz, while a single name in script, such as “Olivia”, looks balanced on 11 oz. If you are buying a matched set, such as a Mr & Mrs pair, both mugs come in the size you choose.
\nFor drinks that leave the house, the deciding question is usually where the cup will sit, not how much it holds.
\nBetween 20 oz and 30 oz on our pet photo and teacher tumblers: 20 oz is the everyday choice and fits more cup holders; 30 oz suits someone who carries water all day and has room on the desk. The 30 oz option costs $5 more.
\nFor young children, smaller and lighter is easier. The 12 oz straw cup with a snap-on lid suits preschoolers; the 16 oz push-button bottle suits a school bag; the 20 oz handle tumbler is for older children who want a cup like the adults’ cups. The 8 oz ceramic cocoa mug is meant for supervised use at home with warm, not boiling, drinks. Whichever you choose, a short first name or nickname in big letters is easiest for a child to recognise.
\nA bigger mug has a larger printable area, so the same text is printed with more space around it. That matters most for:
\nRemember that you type your text in the Order notes box at checkout, and photos are sent by replying to your order confirmation email. We print exactly what you send and do not send proofs, so if you are unsure whether text fits a size, ask us before ordering.
\nIt happens. A 15 oz mug turns out to be too tall for the coffee machine, or a 40 oz tumbler is too big for the cup holder. Here is what to do:
\nChange-of-mind returns, including size changes, come with a free return label. The full steps are on the Returns & Exchanges Policy page.
\nBuying for someone whose coffee habits you do not know? Look at the mugs already on their shelf, or think about how they drink at work. Someone who refills twice before lunch will thank you for 15 oz; someone who drinks a small, strong cup will reach for 11 oz. When in doubt for a family or grandparent mug with several names, 15 oz is the safer pick because the list needs the room anyway. For a teacher, a 20 oz tumbler with a lid survives a busy classroom better than an open mug.
\nWhatever the capacity, care depends on what the item is made of. Ceramic mugs: hand wash recommended to keep the print fresh. Stainless steel travel mugs, tumblers and kids cups: hand wash and never microwave. Heat-reveal mugs: hand wash only, no microwave. Glass: avoid sudden jumps between very hot and very cold. Enamel camp mugs: hand wash; enamel can chip if dropped on hard ground.
\nThe table below lists every product in the shop and the capacity or capacities it comes in. Where two sizes are listed, you choose on the product page. Where a single size is listed, the product is made in that size only.
\nOur FAQs answer common questions about cup holders, dishwashers and photos, and the Help Center has a guide to choosing the right shelf. To browse by shape, start with Mugs, Travel Mugs, Tumblers or Kids Cups. For anything else, email support@mugmellow.shop or use Contact Us.
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