How long will it take for a hairline fracture in a toe to heal?

4-6 weeks. Most hairline fractures heal rather quickly. That said, some fractures seem to take their time and other still will not heal without some "help". Most toe fractures that are not displaced will heal uneventfully, and within 4-6 weeks.
Bone heals in. 6-8 weeks. Smoking, even antiinflammatories can cause delayed healing.

Related Questions

How long does it take a hairline fracture of your foot to heel?

6-8 weeks. Keep in mind weight bearing may delay healing, smoking and low vitamin d can all delay healing.

I can feel a bump on my toe. It still hurts to touch, land a jump or hit my toes. Could it be a hairline fracture?

Get an xray. If the bones in your toes hurt, you should get at least an x-ray. Bones should not hurt to touch. You may benefit from wearing a special boot/shoe to allow you to ambulate while your foot is healing. But the first step imaging studies.
It could be... Have an x-ray taken to find out.

I was told I have a hairline fracture in periosteum of pinky toe. What does that mean? I thought the periosteum was just a fibrous membrane?

You are right. You are right in saying that is not perfect terminology. The doctor may be implying that either you sustained a small occult fracture or that you injured the periosteum which can occur in a bone contusion. Either way, sound like a minor injury which should do well quickly.
Unseen Damage. The periosteum is a fibrous membrane that surrounds the bone surface. It contains many things but mainly has both nerve endings and blood vessels. When the periosteum is damaged it causes pain and feeds blood to the underlying bone. If a hairline fracture is seen on the x-ray, rest assured, the periosteum is also damaged.

Numbness around ankle and side of foot and toes. Not hot or blue. Hairline fracture 7yrs ago. Been lily that all day.

What side of ankle. You could have a compression of either the sural nerve on the outside of the ankle or you could have posterior tibial nerve compression on the inside of the ankle. Either way it is not normal and you should see a podiatrist.

If I have a hairline fracture below my big toe will I need a cast that comes up to my ankle or a cast that comes up to my knee or will I need one at all?

Not at all. Typically nondisplaced fractures of the toes can be treated with a post-op walking shoe or nothing at all depending on the amount of pain you are having.
Often times. A simple surgical shoe may suffice. Or even a camwalker without any cast. Ultimately, it is the decision of the treating doctor.
You may. Need to be in a surgical shoe or boot. Doubt you need a cast.

How would I know if I have a hairline fracture in my foot?

Radiographs. The best (and least expensive) way to determine if you may have a fracture is a simple series of x-rays. If these are not conclusive your doctor may order a more advanced imaging modality (such as an MRI or ct) depending on what exactly your physician is looking for.

How would I know if I have a hairline fracture in my foot?

A foot x-ray. Foot x-rays will diagnose most obvious fractures of the foot. There are less obvious forms of injury, such as a stress fracture that might require specialized testing (such as a bone scan or mri). These can detect bone injury where normal x-rays cannot.
X-ray. Only sure way is to take an x-ray, however in some instances x-ray do not demostrate the fx but clinically you feel there is a fx (stress fx) a bone scan with help in making that diagnosis.