Most box dyes only use peroxide. Depending on the dye, the concentration will vary. 10 vol peroxide (3% solution) is what is used in semi-permanent dyes, and on most hair it isn't very good at lightening. Blondes and some kinds of ash brown hair will find that 10 vol peroxide lightens their hair a great deal. Most dyes that are classed as permanent use 20 vol (iirc 6%) or 30 vol peroxide, and this will lighten many hair colors. Some highlighting formulations and blonde dyes use 40 vol peroxide. This will strip color out of almost any shade of hair. The higher the peroxide concentration, the more damaging the dye is... and the more easily your hair bleaches, the more likely it is to "overreact" to a too strong peroxide concentration.
Most of getting a good dye job with minimal damage is a matter of working with your hair. Since I have the kind of ash brown hair that can lift to white blonde just off 10 vol peroxide, my hair takes dye very easily, and it's not real inclined to let go. Freaking and trying to get rid of a coloring mistake would be a great way to trash my hair. Someone whose hair really resists peroxide and gets their most permanent results with 30 vol will have an easy time "fixing" mistakes, but they'll need to do a lot more upkeep than I do. They'll also find that the standard dye classifications do last about the same as it lists on the box, and it's hard to do wild changes with box dye.
I'm sure some kinds of dye do contain ammonia, but it's not a routine thing.
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