Olaplex N°.4 Bond Maintenance™ Hair Strengthening Shampoo: Repairs Damage & Defend Against Future Breakage | R

★ 4.6 · 78,517 ratings

$34

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The Quick Take

What it is

A color-safe shampoo formulated with coconut oil-derived surfactants to cleanse without stripping moisture. It's for anyone dealing with breakage, frizz, or dryness across all hair types.

Why It Made The Cut

What earns it a place in this cart

90% smoother hair and 49% less breakage when used as a system.

The shampoo that actually strengthens as it cleanses.

Crowd Takeaways

The dominant reaction is Transformed — visible hair improvement.

Our editorial read of how the mood breaks down across this listing’s Amazon ratings — not a poll, not a survey. Positives first, reservations last. Reaction groups, never review quotes.

Transformedvisible hair improvement

Convincedstrength and durability

Reassuredgentle yet effective

Hesitantthe cost barrier

Based on 78,517 Amazon ratings at ★ 4.6

Our Take

A cult favorite that delivers on its promise of stronger, shinier, more manageable hair.

At $34, Olaplex N°.4 is a premium shampoo that justifies its price with clinically proven performance.

At $34 for a single shampoo, it's premium-tier pricing, but the clinical results and massive review count justify the investment for serious breakage concerns.

Who it is forBest for people with damaged, fragile, or breakage-prone hair who are ready to commit to a system approach (or at least pair it with a good conditioner).

How We Judged It

What to check before you buy

Cleansing Power

Coconut oil-derived surfactants

The gentler surfactant base means you're not stripping moisture while you wash. It creates an abundant lather without that tight, squeaky feeling that can worsen breakage. Ideal if you've been burned by harsh cleansers before.

Breakage Reduction

49% reduction in breakage (when used as a system)

That's a measurable claim backed by clinical testing. The shampoo works as part of a trio, so solo use will deliver benefits, but the full N°.3/4/5 system is where the magic compounds. A heads-up if you're looking for a one-step fix.

Hair Feel

90% smoother, better detangling, more conditioned

The result is noticeably smoother strands, easier combing, and a conditioned texture—not stripped. Works on coily, curly, straight, and wavy textures, so there's genuine range here.

Good To Know

Straight from the listing

A highly concentrated, color-safe shampoo proven to reduce breakage and nourish hair leaving it smoother, shinier, and more manageable with every wash.
KEY BENEFITS ✓ Reduces breakage and strengthens hair ✓ Gently cleanses without stripping moisture ✓ Hydrates, smooths, nourishes, and detangles
Clinically Proven 90% smoother, better detangling, more conditioned* 49% reduction in breakage *When used as a system of Nº 3, Nº 4, and Nº 5.
INGREDIENTS Gentle Blend of Coconut Oil-Derived Surfactants Provides an easy, abundant lather that leaves the scalp and hair feeling hydrated.

Manufacturer copy, trimmed. Check the listing for current dimensions and stock.

Context

Where this sits

This isn't a budget bar—it's a targeted treatment shampoo designed to repair damage and prevent future breakage, especially when layered with the full system.