Magnesium Glycinate Price Guide: Per-Capsule Math

Magnesium glycinate is the most-stocked magnesium form in our tracking data — around 2,800 live magnesium offers across retailers at any given time, and more of them are glycinate than any other single form. This week, glycinate bottles with printed counts run from $9.99 to $11.34, and once you divide price by count — and by the real serving size — the cheapest and most expensive ways to buy the same 250 mg serving differ by about 2.2 times.

This guide computes the cost of a 250 mg serving from each bottle's own printed count and per-unit amount, applied to four live deals. Prices were pulled from live retailer listings on October 16, 2026, and re-verified deal-by-deal on October 19, 2026.

What you are actually buying

Magnesium glycinate is magnesium bound to glycine, an amino acid. Labels also print the same ingredient as magnesium bisglycinate, and both names describe the same family of chelated products, so a bisglycinate bottle belongs in any glycinate comparison. Within that constraint, three label details explain most of the price variation:

1. The count and the per-capsule amount. A "120 softgels, 250 mg per serving" bottle and a "300 capsules, 400 mg per capsule" bottle can carry nearly identical sticker prices while holding very different amounts of magnesium. Count times per-capsule amount — not price — is what the comparison below normalizes.

1. The format. Capsules, tablets, and softgels all deliver glycinate. Format changes the per-unit math: softgel and fast-melt formats carry flavoring and delivery systems, while plain capsules are usually the cheapest per unit.

1. What the milligrams count. Some labels state the weight of the whole magnesium compound and some state elemental magnesium, and they do not always say which. When a bottle does not print that line, its per-milligram math is not comparable — so every table below uses each bottle's own printed numbers and nothing inferred.

One more trap to rule out before comparing: check whether the dose on the front is per capsule or per serving. A softgel bottle that reads "250 mg per serving" may mean one softgel — or two. The Horbaech bottle in the table below is exactly that case. Count units, not servings, when you compare.

The only math that matters: cost per 250 mg serving

Per-bottle prices are designed to confuse comparison. The formula:

Cost per 250 mg serving = price ÷ (count × mg per capsule) × 250

A 250 mg serving is the most common single-capsule strength on shelf, so it works as a common ruler across bottles labeled 100, 250, or 400 mg per capsule. Applied to this week's live single-form glycinate bottles with printed counts:

Read the right-hand column, not the price column. The two 100-mg-per-unit bottles cost about ten percent more on the sticker than the Nobi bottle, yet a 250 mg serving from them costs nearly twice as much, because a small per-capsule amount has to be bought over and over to reach the same serving. The softgel row is the serving-line trap live: the label reads 250 mg per serving, the brand's own directions set a serving at two softgels, so the true per-softgel amount is 125 mg and a mid-pack sticker lands at the most expensive per-serving rate in the table.

Where the bulk option fits

Bulk value comes from count times true per-unit strength — not from the unit count alone — and this week's table proves it both ways. The biggest bottle, the 120-softgel Horbaech, holds exactly as many 250 mg servings as the 60-capsule Nobi bottle (sixty), because its serving is two softgels. Nobi wins the per-serving column at the guide's lowest sticker, and the only way to beat it is to leave glycinate for the oxide shelf below. When a bulk bottle is genuinely bulk — high per-unit strength times a large count — sticker noise matters far less than count.

The cheap-form price floor: citrate and oxide

Glycinate usually carries a premium over the older magnesium forms, so the honest comparison needs the floor priced in. The same math applied to this week's cheapest citrate and oxide bottles:

Two things stand out. Even inside the cheap forms the spread is about 6 times, because count still rules everything. And the cheapest way to a 250 mg serving this week is not glycinate at all: the best glycinate rate in the first table is $0.167 per serving, while the oxide floor hits about $0.06 — the cheap-form floor undercuts the best glycinate rate by nearly three times. At these counts, the form premium is smaller than the count penalty.

The threonate premium

Magnesium L-threonate is the newest and most expensive form on the shelf. This week's tracked threonate bottles run from $31.50 to about $42 — roughly three to four times the sticker of the glycinate bottles above — and fewer of them print a per-capsule amount. The Nutricost Magtein bottle below is the exception: 90 capsules at 666 mg each works out to about $0.389 per capsule. That is the format premium in one number: a single threonate capsule costs more than two 250 mg glycinate servings at the table's best rate. Whether that premium is worth paying is not a question this guide answers — prices and counts are all it compares.

The annual math: what a one-a-day habit costs

If you take one 250 mg serving a day, a year is 365 servings. Applied to the glycinate table:

The spread that looked like a dollar on the sticker ends the year more than $70 apart — and the softgel bottle that seemed mid-pack at the register costs more than double the Nobi bottle over a year, purely because its serving is two units. Small bottles of small-strength capsules are the most expensive habit in this category — the same pattern as the D3 and B12 guides, and the reason the annual row belongs in every price comparison. If your serving is larger than the label's, scale every annual number the same way; the ranking does not change.

How to rank any bottle in ten seconds

1. Find the count and the per-capsule (or per-tablet, per-softgel) amount on the label — both numbers, not the front-panel dose.

1. Divide price by count for the per-unit cost; multiply by the number of units in your serving for the per-serving cost.

1. Check the serving line: per capsule is not per serving on softgel and gummy bottles.

1. Project the year: annual cost = per-serving cost × 365.

Where to track magnesium prices over time

One-off deal pages go stale. If you buy magnesium regularly, the smarter habit is a page that refreshes:

• The magnesium ingredient page lists every magnesium offer currently tracked on the site, filterable by form and retailer.

• The capsule supplement deals hub rounds up current capsule-format offers across ingredients.

• The site-wide deals page is the front door for everything tracked across all supplement categories.

The short version

Magnesium glycinate is a commodity: confirm the count and the per-capsule amount, confirm the serving line, then buy the lowest price per 250 mg serving in a count you will finish. Today that means the 60-capsule Nobi Nutrition bottle at about seventeen cents per serving — the best glycinate rate this week — with the 100-mg capsules from 21st Century and NOW Foods at about thirty cents once the serving math is applied, and the 120-softgel Horbaech bottle at about thirty-six cents once its two-softgel serving is counted. The oxide and citrate floors at six to eleven cents per serving beat every glycinate bottle in the guide if the form premium does not fit the budget. Recheck the live table before you buy — prices on this page move with the market.

Prices in this guide were verified against live retailer listings on October 16, 2026, and re-verified deal-by-deal on October 19, 2026; they change frequently. This article describes products, prices, and label content only; it is not medical advice, and you should consult a qualified professional with any health questions before starting any supplement.

Read next: Creatine Monohydrate Guide: Price Per Serving — the same per-unit math applied to the sports-nutrition aisle — Mass Gainer vs. Whey Protein: How to Choose for the protein comparison — Vitamin D3 5000 IU: How to Pay Less Per Capsule for the vitamin-aisle version of the per-unit method — and Vitamin B12 1000 mcg Price Guide: Per-Unit Math for the newest entry in the series.