Casio A158WA-1 – 33mm Digital Watch | 7-Year Battery | Alarm
Some watches become classics because of complicated movements or expensive materials. The Casio A158 has managed it by doing almost the complete opposite. Its compact digital display, slim chrome-finished case and simple steel bracelet have changed very little over the years, creating an inexpensive everyday retro styling as it is for its practicality.
The case measures 33.2mm across and 36.8mm from top to bottom, making the A158 genuinely compact by modern standards. At only 8.2mm thick, it also sits exceptionally slim and should slide underneath a shirt cuff without any difficulty. Then there is the weight; at approximately 46g including the bracelet, the A158 is extremely light compared with most conventional steel watches. This makes it particularly easy to wear throughout the day and a good option for smaller wrists, although anyone accustomed to the weight of a full stainless-steel sports watch may initially find it surprisingly light. The low weight is partly explained by the construction; the bracelet itself is stainless steel, but the silver-coloured case and bezel are made from resin with a chrome-plated finish rather than solid stainless steel.
Inside is a Casio quartz digital movement powered by a CR2016 battery. Quartz means the watch uses an electronic oscillator rather than a mechanical movement, providing far more consistent everyday accuracy without requiring winding or regular wear to keep it running. Casio officially rates the A158 to approximately ±30 seconds per month and estimates around seven years of battery life under normal use which means you can leave it in a drawer for weeks, pick it back up and reasonably expect it still to be showing the correct time.
The display provides considerably more information than a conventional three-hand watch. Hours, minutes and seconds are shown alongside the day and date, giving you most of the information you are likely to need without moving between different screens. You can choose between 12- and 24-hour time formats, while an automatic calendar keeps track of the date. February is fixed at 28 days, so the date may require manual correction during leap years, but otherwise there is very little to think about once everything has been set. There is also a daily alarm and an optional hourly time signal. Neither is particularly sophisticated by modern smartwatch standards, but both remain genuinely useful and are part of what makes a simple Casio digital watch more functional than its price might suggest. The stopwatch measures in 1/100-second increments and can run for up to 59 minutes and 59.99 seconds. It supports elapsed time, split timing and first- and second-place measurements, making it considerably more capable than simply adding a decorative 'chrono' label to the dial. The stopwatch can be useful for exercise, cooking, timing a journey or anything else where you want a simple timer immediately available on your wrist without reaching for a phone.
A green LED light illuminates the display in darkness. This is worth distinguishing from the lighting system used by the slightly larger Casio A168. The A158 uses a simpler LED light rather than the A168's electro-luminescent display illumination. The A168 therefore provides the better night-time display, while the A158 counters with a slimmer 8.2mm case and slightly lower 46g weight. Neither approach is automatically better; it depends on whether compactness or stronger illumination matters more to you. Above the digital display is resin glass. Like the case, this helps keep the watch light and inexpensive, but it is more susceptible to surface scratching than mineral or sapphire crystal. For an inexpensive Casio, however, there is an argument that this actually fits the character of the watch. The A158 is designed to be worn rather than protected, and minor marks tend to become part of an everyday watch that costs relatively little to replace.
The bracelet is stainless steel and uses Casio's adjustable clasp. Rather than requiring individual links to be removed in the same way as many conventional steel bracelets, the clasp can be repositioned along the bracelet to achieve the required size which makes initial adjustment relatively straightforward and also allows the watch to retain the metallic appearance that has become such an important part of the A158's retro character.
The bracelet itself is relatively thin and light rather than heavily engineered. Anyone expecting the solid links and substantial clasp of an expensive sports watch will immediately notice the difference, but adding that sort of construction would rather defeat the point of such a small and lightweight Casio.
Water resistance is where expectations need to remain sensible. Casio officially describes the A158 simply as water resistant without providing a numerical depth rating. I would therefore be perfectly comfortable with rain, hand washing and ordinary accidental splashes, but I would not choose the A158 specifically for swimming. Anyone wanting an inexpensive Casio for regular water use would be better served by one of the brand's models with a clearly stated 50m, 100m or greater rating.
And that is really where the A158 makes sense. It is not pretending to be a miniature luxury watch and it does not need an automatic movement or sapphire crystal to justify itself. It is a genuinely established Casio design that happens to remain extremely affordable. The digital movement is accurate, the battery can last for years and the alarm, stopwatch, calendar and 12/24-hour display provide far more functionality than many conventional analogue watches. Its compact dimensions are also increasingly distinctive. At a time when even simple everyday watches regularly measure 40mm or more, a 33.2mm case feels deliberately retro rather than merely small. This makes it particularly suitable for smaller wrists, but it does not need to be treated purely as a small-wrist watch. The rectangular digital case follows a completely different set of visual proportions from a conventional round watch, and the compact dimensions are a fundamental part of the A158's design.
For someone looking for their first proper everyday watch and prioritising simplicity, accuracy and low cost, that makes the Casio particularly difficult to argue against. It is small enough to wear almost anywhere, useful enough to do considerably more than simply tell the time and inexpensive enough that you do not need to become precious about actually using it. It also makes a surprisingly good second or third watch for someone who already owns more expensive pieces. There are plenty of occasions when the best watch is simply the one you can put on, forget about and trust to still show the correct time.
Included in the box:
Casio A158WA-1 digital watch and accompanying Casio packaging and documentation.
Worth knowing:
The A158WA-1 measures approximately 33.2mm across, 36.8mm from top to bottom and only 8.2mm thick, with a total weight of around 46g. It is deliberately compact and lightweight rather than designed to provide the wrist presence of a modern steel sports watch.
The stopwatch measures in 1/100-second increments for up to 59 minutes and 59.99 seconds.
