Hair oils can be surprisingly unpredictable. One formula disappears into the lengths and leaves them glossy and soft; another turns a perfectly good hair day into an oily situation within seconds.

These four options cover both extremes, with two clear standouts for lightweight shine and repair.

1. L’Oréal Paris Extraordinary Oil

Price: €12.40

Rating: 10000/10

The L’Oréal Paris Elseve Extraordinary Oil is easily one of the most impressive affordable options in this group. The formula feels light rather than syrupy, spreads easily through the lengths and gives dry hair a noticeably softer, shinier finish. L’Oréal recommends using a few drops on damp or dry hair, particularly through the lengths and ends.

What makes it such a strong everyday choice is how little effort it requires. It smooths without immediately making the hair look greasy, helps calm frizz and leaves behind a noticeable fragrance. For the price, it delivers the kind of polished finish usually associated with much more expensive oils.

2. TRESemmé Keratin Smooth Oil

Price: around €10

Rating: 1/10

The TRESemmé Keratin Smooth Oil unfortunately lands at the opposite end of the ranking. Although the texture initially feels fairly fluid and lightweight, even a small amount can become too much very quickly.

On finer or easily weighed-down hair, one drop may leave the lengths looking noticeably oily rather than softly glossy. The runny consistency also makes portion control more difficult, so this is definitely the product here that requires the lightest hand. For this particular hair type, however, it simply felt too heavy to justify the effort.

3. K18 Molecular Repair Hair Oil

Price: €29.90

Rating: 10/10

The K18 Molecular Repair Hair Oil is expensive for such a tiny bottle, but this is also an extremely concentrated formula. It is designed to strengthen damaged hair, reduce frizz and improve softness without adding much weight. The brand recommends starting with just one to three drops.

That tiny dosage is exactly what makes the price easier to understand. A couple of drops spread surprisingly well, so the bottle lasts much longer than its size suggests. The finish feels lightweight and smooth rather than coated, making this especially appealing for damaged or frequently styled hair that still hates heavy oils.

4. Olaplex No.7 Bonding Oil

Price: €32

Rating: 10000/10

The Olaplex No.7 Bonding Oil is the other clear favourite. Despite looking rich in the bottle, it feels remarkably light once distributed through the hair. Only two or three drops are recommended, and the formula is designed to boost shine, soften the lengths, control frizz and provide heat protection up to 232°C.

This is the kind of oil that works especially well as a finishing step. It smooths flyaways without flattening the hair and gives the lengths that glossy, freshly styled look without an obvious greasy film. A small bottle also goes a surprisingly long way because so little product is needed each time.

For an affordable everyday option, L’Oréal Extraordinary Oil is difficult to beat. If damaged hair is the priority, K18 earns its place despite the higher price. Olaplex No.7 is the strongest all-rounder for lightweight shine and frizz control, while the TRESemmé oil is the one I would skip if your hair becomes greasy or weighed down easily.