Measured: Solid precious metal is declared by a fineness stamp, karat for gold and parts per thousand for silver. A plated finish is declared instead by its coating thickness in microns.
Measured: Case size is quoted in millimeters across the case, excluding the crown. Round cases quote a diameter, and the rest quote width by height. Lug to lug length decides whether it fits your wrist.
Measured: Accuracy is stated in seconds per day for mechanical movements and seconds per month for quartz. A COSC certified chronometer must run within minus 4 and plus 6 seconds a day.
The basics
What to know about watches
A machine you wear
A watch is a small machine you strap to your body and then expect to run without stopping. Inside a sealed case sits the movement, the engine that counts seconds and drives hands across a dial or digits across a screen. A crystal covers the front, a caseback closes the rear, rubber gaskets squeeze between them, and two lugs hold whatever wraps your wrist. Nothing else in this category has to keep working to be worth owning. This is the real line between a watch and a bracelet. It explains how two pieces that look alike from three feet away sit fifty times apart in price.
Settle the movement first
Movement type sets cost, accuracy and every bill that follows, so settle it first. Quartz drives a battery current through a crystal cut to vibrate 32,768 times a second, holds time to about 15 seconds a month, and needs a fresh cell every two to five years. A mechanical watch stores energy in a coiled mainspring and lets it out through gears governed by a balance wheel that swings back and forth. The automatic version adds a weighted rotor that rewinds the spring from the motion of your arm. Accuracy there runs much wider, often 20 seconds slow to 40 fast per day, tightening to 4 and 6 on a certified chronometer. Solar sits between them, charging a cell through a translucent dial.
Case, glass and water rating
Everything around the movement is armor with published limits. Steel cases mostly use grade 316L for its corrosion resistance, titanium sheds close to 40 percent of that weight while showing scratches more openly, and plated brass rubs back to yellow at the case edges within a year or two of daily wear. Crystals come in three materials: acrylic scuffs from a sleeve and buffs clean with a mild polish, mineral glass resists more and keeps every scratch it takes, and sapphire measures 9 on the Mohs hardness scale, above the quartz grit in sand at 7. Read water ratings hardest, since they come from a static pressure test on a new watch in a lab, not a depth you can swim to. Thirty meters, or 3 ATM, allows rain and hand washing. Fifty meters adds accidental immersion. Swimming wants 100 meters and a crown that screws down, and scuba wants a watch marked DIVER'S to the ISO 6425 standard, most of which are rated 200 meters.
Which watch for your week
Choose the family by the week you actually have. Tailoring and interviews want the dress watch, thin enough to pass under a buttoned cuff. First serious buys usually land on the field watch, whose full numerals read instantly in bad light. Water, weekends and one watch for everything point at dive style, while gyms, building sites and children suit the resin sport watch that survives a drop. Training data, alerts and payments belong to the smartwatch and its nightly charge. Two families put jewelry ahead of timekeeping: the bracelet watch, sized by removing links to match your other metal, and the bangle watch, a rigid cuff that sizes to your knuckles. Wrist measurement narrows the rest, since a 6 inch wrist carries 34 to 38 mm and a 7.5 inch wrist takes 42 mm and up.
What a depth rating costs
Each gain gets paid for somewhere else. Depth rating costs thickness, since heavier gaskets, a screwed caseback and a screw down crown push a 200 meter case past 12 mm. That will not clear a shirt cuff a 7 mm dress case slips under. Mechanical charm costs money on a schedule, a few hundred dollars of service every five to seven years, against a battery and a fresh seal on quartz. Sapphire resists scratching and stays brittle, chipping at the edge from a knock that would only dent acrylic. Steel bracelets add 60 to 80 grams over leather, which reads as quality in the shop and as weight by 4 pm. Smartwatches do more than any of them and expire like phones.
Five minutes in your hand
Five minutes in hand settles most of it. Set the hands to exactly 12. The minute hand should cover the marker dead on and the date should sit square in its window, since loose alignment is the clearest sign of rushed assembly. Angle the dial under a lamp and study the printed text near the edge for fuzzy or doubled strokes. Thread a screw down crown home and feel whether it catches smoothly, since a crown that cross threads is how water beats a rating. Read the caseback, where the water figure is stamped, and treat a watch carrying no figure anywhere as having none. Lug width matters too, so favor an even number like 18, 20 or 22 mm, because odd widths make replacement straps hard to find.
Seals, magnets and batteries
Longevity comes down to seals, magnets and batteries. Gaskets flatten and dry out from the day a watch leaves the factory, so anything you swim in wants a pressure test every couple of years. Magnetism is the invisible fault: phone speakers, laptop lids and magnetic bag clasps can magnetize a balance spring badly enough to add minutes a day, and a jeweler clears it in seconds. Pull a dead quartz cell within weeks rather than leaving it in place, since a leaking battery corrodes a movement and turns a small job into a large one. Book a mechanical service as maintenance on a schedule rather than a repair after failure, because dry oil lets steel grind against steel.
Buyer checklist
Before you buy watches
Separate appearance from material value. Metal, finish, stone details and aftercare matter more than a style name alone.
01
Confirm the material
Look for clear wording such as solid, sterling, filled, vermeil, plated or tone. These terms describe different constructions and wear lives.
02
Ask what is treated or lab-grown
Stone identity, treatments and laboratory origin should be disclosed when they affect value or care.
03
Check dimensions and weight
Chain length, hoop diameter, ring width, watch case size and total weight change comfort as much as appearance.
04
Review service and returns
Check resizing, battery or movement service, plating repair, warranty exclusions and the return rules for personalized pieces.
Wrap a tape around your wrist just past the bone: under 6.5 inches sits best with a 34 to 38 mm case, 6.5 to 7.5 inches suits 38 to 42 mm, and only above that does 42 mm and larger stop looking oversized.
Measure lug to lug, the span from the tip of the top strap lug to the tip of the bottom one, and compare it with the flat width across your wrist. Anything longer hangs over the edge and rocks, whatever the case diameter promises.
Button a shirt cuff over the watch before you buy it. Cases past about 12 mm thick catch on the cuff edge every time you reach for something.
Size a metal bracelet in the late afternoon and leave enough play to slide it about half an inch along your wrist. Wrists swell measurably in heat, and a bracelet fitted tight in a cool morning bites by evening.
Buckle a leather strap on the middle hole rather than the last one. You keep adjustment in both directions as your wrist changes through the day.
Check the lug width in millimeters before you count on changing straps, since 18, 20 and 22 mm are stocked everywhere while 19 and 21 mm leave you hunting.
Care
Caring for watches
Rinse the case, crystal and bracelet under fresh warm water after a sea or pool swim, then dry them, because salt and chlorine dry into crystals in the gasket groove and cut the seal.
Never turn the crown or press a button while the watch is wet. The crown tube is the largest opening in the case, and an unscrewed crown lets water straight past the seal.
Keep leather straps out of water completely, since sweat and soap rot the stitching from the inside and a soaked strap dries stiff and splits at the lug holes.
Wipe the caseback and the skin side of the bracelet at the end of a hot day, as sweat sits trapped against the metal there and pits plating first.
Wind an automatic 20 to 30 turns before setting it after a spell in a drawer, and avoid changing the date between 9 pm and 3 am, when the date wheel is already engaged and its teeth strip easily.
Store watches out of direct sun and away from radiators, because ultraviolet light fades dials and printed markers while heat thins the oil inside a movement.
Questions
Common questions
What does 50 meter water resistance actually let me do?
Less than the number suggests. That figure comes from a static pressure test on a new watch, not from a depth you can reach. Fifty meters covers rain, hand washing and accidental immersion, and there it stops. Swimming asks for 100 meters and a crown that screws down, while scuba asks for 200 meters carrying a DIVER'S marking to the ISO 6425 standard.
Can I shower with my watch on?
Better not, whatever the rating says. Hot water expands the case and the gaskets at different rates and opens the seal for a moment, and soap strips the grease that keeps a gasket supple. Steam is worse, because vapor passes through gaps that liquid water would not. Take the watch off first, and keep leather straps out of the bathroom entirely.
Quartz or automatic for a first good watch?
Quartz if you want it right without thinking about it: roughly 15 seconds a month, a battery every few years, nothing else. Automatic if the machine itself is the reason you are buying. An automatic runs 38 to 70 hours off the wrist and then stops. A watch worn twice a week needs resetting each time, and a service every five to seven years costs a few hundred dollars.
What size watch should I wear?
Two numbers decide it, and diameter is the less important one. Measure your wrist first, since under 6.5 inches suits 34 to 38 mm and 6.5 to 7.5 inches suits 38 to 42 mm. Then measure lug to lug, the span from the tip of one strap lug to the tip of the opposite one. Anything longer than the flat width across your wrist overhangs and rocks.
Is sapphire crystal worth the extra money?
On a watch you wear daily, yes. Sapphire sits at 9 on the Mohs hardness scale and the quartz in ordinary sand and dust sits at 7. It stays clear for years while mineral glass collects fine scratches that never come out. Brittleness is the catch, as sapphire chips at the edge from a sharp knock where acrylic only dents and polishes back.
How often does a mechanical watch need servicing?
Every five to seven years for most, and it counts as maintenance rather than repair. The oils inside thin out and dry, and once they are gone the steel pivots grind in their bearings and wear parts that then need replacing. Budget a few hundred dollars for a common movement. Quartz has no equivalent bill and asks only for a battery and a fresh seal.
Which wrist should a watch go on?
Most people use the non dominant wrist, the left for right handers, because the watch takes fewer knocks there and a crown at the 3 o'clock position does not press into the back of your hand when you bend it. Left handers can wear it on the right and reach across to set it, or buy a watch built with the crown at 9 o'clock.
Why is my automatic suddenly running fast?
Magnetism is the usual answer. A balance spring that picks up a field from a phone speaker, a laptop lid or a magnetic bag clasp sticks to itself and effectively shortens, and the watch can gain several minutes a day. Any jeweler can demagnetize it in under a minute. Running slow instead points the other way, toward old oil and a service due.
