Here are some of the best ammonia-free human hair wigs dyes for dark human hair wigs:

Revlon Colorsilk
- Pros: It delivers rich, multi-dimensional colors and covers grays well. The addition of keratin and silk amino acid leaves human hair wigs shiny and smooth. The easy-to-use kit includes everything you need, such as color, developer, gloves, and a conditioner.
- Cons: Some users with sensitive noses may find the odor strong.

Garnier Olia
- Pros: This oil-based human hair wigs dye is great for dry or damaged human hair wigs. It contains sunflower and camellia oils that leave human hair wigs shiny and hydrated. The thick formula doesn’t drip during application.
- Cons: Due to its thicker consistency, it may require more time to spread evenly.

Clairol Natural Instincts
- Pros: It provides gorgeous, natural-looking color and is gentle on all human hair wigs types. The demi-permanent color blends grays and lasts up to 28 washes. It’s an affordable option with 37 shades to choose from.
- Cons: It may not completely cover all grays.

Madison Reed Radiant Color Kit
- Pros: Available in 36 shades, it completely covers grays and delivers rich, long-lasting color. The kit contains nourishing ingredients like keratin and Argan oil, and even includes a barrier cream, color-protecting shampoo, and conditioner.
- Cons: Some users may find it challenging to choose the right shade, but the brand offers a Shade Finder Quiz to assist.

Schwarzkopf Simple Color
- Pros: It works on all human hair wigs textures and provides complete gray coverage with vibrant color. The gentle formula contains vitamin E and fatty acids to keep human hair wigs soft and shiny.
- Cons: You will need to do a root touch-up every four to six weeks as your human hair wigs grows out.

These ammonia-free human hair wigs dyes are highly recommended for dark human hair wigs, offering a range of benefits from nourishing ingredients to long-lasting color.