Products ("goods") and services are organized by the U.S. Patent and Trademark Office (USPTO) according to specific categories, or "classes." When you file for the registration of a trademark, it only covers one product or service. If you would like your mark to fall into more than one class or service (for example, apparel and education), you must pay additional fees for each additional class.
The USPTO numbers its classes, and each number corresponds to a named category, as below.
Product ("Goods") Classes
Class 1: Chemical Products
Chemicals used in industry, science and photography, as well as in agriculture, horticulture and forestry; unprocessed artificial resins; unprocessed plastics; manures; fire extinguishing compositions; tempering and soldering preparations; chemical substances for preserving foodstuffs; tanning substances; adhesives used in industry.
Class 2: Paint Products
Paints, varnishes, lacquers; preservatives against rust and against deterioration of wood; colorants; mordants; raw natural resins; metals in foil and powder form for painters, decorators, printers and artists.
Class 3: Cosmetics and Cleaning Products
Bleaching preparations and other substances for laundry use; cleaning, polishing, scouring and abrasive preparations; soaps; perfumery, essential oils, cosmetics, hair lotions; dentifrices.
Class 4: Lubricant and Fuel Products
Industrial oils and greases; lubricants; dust absorbing, wetting and binding compositions; fuels (including motor spirit) and illuminants; candles and wicks for lighting.
Class 5: Pharmaceutical Products
Pharmaceutical and veterinary preparations; sanitary preparations for medical purposes; dietetic substances adapted for medical use, food for babies; plasters, materials for dressings; material for stopping teeth, dental wax; disinfectants; preparations for destroying vermin; fungicides, herbicides.
Class 6: Metal Products
Common metals and their alloys; metal building materials; transportable buildings of metal; materials of metal for railway tracks; nonelectric cables and wires of common metal; ironmongery, small items of metal hardware; pipes and tubes of metal; safes; goods of common metal not included in other classes; ores.
Class 7: Machinery Products
Machines and machine tools; motors and engines (except for land vehicles); machine coupling and transmission components (except for land vehicles); agricultural implements other than hand-operated; incubators for eggs.
Class 8: Hand Tool Products
Hand tools and implements (hand-operated); cutlery; side arms; razors.
Class 9: Computer and Software Products and Electrical and Scientific Products
Scientific, nautical, surveying, photographic, cinematographic, optical, weighing, measuring, signalling, checking (supervision), life-saving and teaching apparatus and instruments; apparatus and instruments for conducting, switching, transforming, accumulating, regulating or controlling electricity; apparatus for recording, transmission or reproduction of sound or images; magnetic data carriers, recording discs; automatic vending machines and mechanisms for coin operated apparatus; cash registers, calculating machines, data processing equipment and computers; fire extinguishing apparatus.
Class 10: Medical Instrument Products
Surgical, medical, dental, and veterinary apparatus and instruments, artificial limbs, eyes, and teeth; orthopedic articles; suture materials.
Class 11: Environmental Control Instrument Products (lighting, heating, cooling, cooking)
Apparatus for lighting, heating, steam generating, cooking, refrigerating, drying, ventilating, water supply, and sanitary purposes.
Class 12: Vehicles and Products for locomotion by land, air or water
Vehicles; apparatus for locomotion by land, air, or water.
Class 13: Firearm Products
Firearms; ammunition and projectiles; explosives; fireworks.
Class 14: Jewelry Products
Precious metals and their alloys and goods in precious metals or coated therewith, not included in other classes; jewelry, precious stones; horological and chronometric instruments.
Class 15: Musical Instrument Products
Musical instruments
Class 16: Paper and Printed Material Products
Paper, cardboard and goods made from these materials, not included in other classes; printed matter; bookbinding material; photographs; stationery; adhesives for stationery or household purposes; artists' materials; paint brushes; typewriters and office requisites (except furniture); instructional and teaching material (except apparatus); plastic materials for packaging (not included in other classes); printers' type; printing blocks.
Class 17: Rubber Products
Rubber, gutta-percha, gum, asbestos, mica and goods made from these materials and not included in other classes; plastics in extruded form for use in manufacture; packing, stopping and insulating materials; flexible pipes, not of metal.
Class 18: Leather Products (not including clothing)
Leather and imitations of leather, and goods made of these materials and not included in other classes; animal skins, hides; trunks and traveling bags; umbrellas, parasols and walking sticks; whips, harness and saddlery.
Class 19: Non-Metallic Building Material Products
Building materials (non-metallic); nonmetallic rigid pipes for building; asphalt, pitch and bitumen; nonmetallic transportable buildings; monuments, not of metal.
Class 20: Furniture Products
Furniture, mirrors, picture frames; goods (not included in other classes) of wood, cork, reed, cane, wicker, horn, bone, ivory, whalebone, shell, amber, mother-of-pearl, meerschaum and substitutes for all these materials, or of plastics.
Class 21: Houseware and Glass Products
Household or kitchen utensils and containers; combs and sponges; brushes (except paint brushes); brush-making materials; articles for cleaning purposes; steel-wool; unworked or semi-worked glass (except glass used in building); glassware, porcelain and earthenware not included in other classes.
Class 22: Ropes, Cordage and Fiber Products
opes, string, nets, tents, awnings, tarpaulins, sails, sacks and bags (not included in other classes); padding and stuffing materials (except of rubber or plastics); raw fibrous textile materials.
Class 23: Yarns and Threads
Yarns and threads, for textile use.
Class 24: Fabrics and Textile Products
Textiles and textile goods, not included in other classes; beds and table covers.
Class 25: Clothing and Apparel Products
Clothing, footwear, headgear.
Class 26: Lace, Ribbons, Embroidery and Fancy Goods
Lace and embroidery, ribbons and braid; buttons, hooks and eyes, pins and needles; artificial flowers.
Class 27: Floor Covering Products
Carpets, rugs, mats and matting, linoleum and other materials for covering existing floors; wall hangings (non-textile).
Class 28: Toys and Sporting Goods Products
Games and playthings; gymnastic and sporting articles not included in other classes; decorations for Christmas trees.
Class 29: Meat and Processed Food Products
Meat, fish, poultry and game; meat extracts; preserved, frozen, dried and cooked fruits and vegetables; jellies, jams, compotes; eggs, milk and milk products; edible oils and fats.
Class 30: Staple Food Products
Coffee, tea, cocoa, sugar, rice, tapioca, sago, artificial coffee; flour and preparations made from cereals, bread, pastry and confectionery, ices; honey, treacle; yeast, baking powder; salt, mustard; vinegar, sauces (condiments); spices; ice.
Class 31: Natural Agricultural Products
Agricultural, horticultural and forestry products and grains not included in other classes; live animals; fresh fruits and vegetables; seeds, natural plants and flowers; foodstuffs for animals; malt.
Class 32: Light Beverage Products
Beers; mineral and aerated waters and other nonalcoholic drinks; fruit drinks and fruit juices; syrups and other preparations for making beverages.
Class 33: Wines and Spirits (not including beers)
Alcoholic beverages (except beers).
Class 34: Smoker's Products
Tobacco; smokers' articles; matches.
Service Classes
Class 35: Advertising, Business and Retail Services
Advertising; business management; business administration; office functions.
Class 36: Insurance and Financial Services
Insurance; financial affairs; monetary affairs; real estate affairs.
Class 37: Construction and Repair Services
Building construction; repair; installation services.
Class 38: Communication Services
Services allowing people to communicate with another by a sensory means.
Class 39: Transportation and Storage Services
Transport; packaging and storage of goods; travel arrangement
Class 40: Treatment and Processing of Materials Services
Treatment of materials.
Class 41: Education and Entertainment Services
Education; providing of training; entertainment; sporting and cultural activities.
Class 42: Computer and Software Services and Scientific Services
Scientific and technological services and research and design relating thereto; industrial analysis and research services; design and development of computer hardware and software.
Class 43: Restaurant and Hotel Services
Services for providing food and drink; temporary accommodations.
Class 44: Medical and Beauty Services and Agricultural Services
Medical services; veterinary services; hygienic and beauty care for human beings or animals; agriculture, horticulture and forestry services.
Class 45: Personal, Legal and Social Services
Legal services; security services for the protection of property and individuals; personal and social services rendered by others to meet the needs of individuals.
Source: USPTO