Electric toothbrush model numbers, decoded

Two things make electric toothbrush shopping harder than it needs to be. The first is that the brands name their ranges by number, so a 5300 and a 5900 sound like neighbours when they are three years and two features apart. The second is that the model number printed on the box describes the package, not the brush. A different colour, an extra head or a travel case gets a new number, and the motor inside does not change.

Type whatever is on your box into the box below.

How Philips numbers work

Every Sonicare handle has a code beginning HX. The useful thing to know is that the HX number identifies the package. Philips keeps a marketing name for the brush itself, such as 4100, 5300, 5900, 7300 or 9900 Prestige, and then issues HX codes for each box of that brush.

The practical consequences:

• Two HX numbers can be the same brush. On Amazon US the Sonicare 4100 sells as both HX3681 and the July 2026 HX4031, side by side, at the same price. The HX4031 adds three intensities and an EasyStart ramp. The older one is not a fake or a grey import.
• A high number is not a high tier. On the listings we checked, the 5900 is HX7133 and the 7300 is HX7421, so the first two digits rank nothing. The 9900 Prestige is HX9990 and the Next-Gen version of it is HX9834, which is a lower number for a newer brush.
• The codes on the brushes we track. Sonicare 4100 is HX3681, 5300 is HX6423, 5900 is HX7133, 7300 is HX7421, 9900 Prestige is HX9990 and the Next-Gen Prestige is HX9834. The kids’ brushes are HX6321 and, for the Design a Pet edition, HX3601.
• Club store bundles get their own code. Two handles, four heads and a second case in one box will carry a number you will not find in any review. That is normal and usually good value, since the handle is standard.
• Head packs also start with HX. The three head packs we priced on October 30 were HX9042, HX9044 and HX9094. A code starting HX90, a low price and a row of heads in the photo together mean you are buying refills rather than a brush.

How Oral-B numbers work

Oral-B splits into two worlds, and the split is the single most expensive thing to get wrong.

iO handles use a magnetic drive and take iO heads. Their codes look like iO G3.2Q6.2KD or iOM9.4B2.2A. The letters and digits after the series number describe colour and box contents. An iO3 in a different colour with two heads is a different code and the same brush.

Classic handles are everything else: Vitality, Pro 1000, Pro 3, Smart, Genius. They are geared rather than magnetic, they are louder, and they take round heads with a classic shaft. These show up as D codes. The Oral-B kids’ rechargeable we track is D100.413.2K, and the same D prefix runs through the adult classic range.

An iO head will not fit a classic handle and a classic head will not fit an iO. If you have a drawer of round heads, that is an argument for staying classic, and a real one: round heads cost about $12.49 each where iO heads cost about $10.20, but you already own the old ones.

Head codes are not brush codes

This trips people up in search results, because a head pack and a handle look alike in a thumbnail.

The Sonicare list is more forgiving than the pricing suggests. A C2 head from a 4100 clicks onto a Prestige 9900 perfectly well, so the A3 head that ships with the expensive handles is a choice rather than a requirement. That one fact is worth about $5 a head.

Reading a listing title in ten seconds

Listing titles are written for the search box, not for you. The order that actually tells you what you are buying:

1. The range name. 4100, 5900, iO3, Pro 1000. This is the brush.
2. The number of handles. “2 pack” doubles the price and halves the confusion once you spot it.
3. How many heads. The main reason two listings for the same brush differ by $30.
4. Case or no case. Travel cases add about $20 and charging cases much more.
5. The model code. Useful for matching against a review, useless as a measure of quality.

When a different number really is a different brush

Three times in the past year the number change mattered, which is why it is worth checking rather than assuming:

• Sonicare 9900 Prestige. Since August 31, 2026 there are two of them. The original HX9990 and the Next-Gen HX9834 sell at the same price, and the Next-Gen has a screen on the handle and eight modes. Our old versus Next-Gen page shows how to tell them apart in a thumbnail.
• Sonicare 4100. HX4031 has three intensities, HX3681 has two. Same price, so take the newer one.
• SURI. The S2, sold as the SURI Pro, replaced what older reviews call the Suri 2.0 and added a pressure sensor. A review of the old one does not describe the new one.

Store exclusives and why they exist

Warehouse clubs and big-box chains ask for a bundle nobody else has, so the brand builds one: the same handle, two of them, an extra case and a model number unique to that chain. It is a real brush with a full warranty. It is also why you cannot find a review of it, and why the honest answer when someone asks whether the club store version is any good is to work out which standard handle it is and read about that instead.

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