Q and A


What is a normal CD4 count, CD4% and CD4:CD8 ratio?


After finding out you are HIV positive, your doctor will run several blood tests.

One will be for your immune system and will include your CD4 and CD8 count. Of these, the CD4 count is the most important main result but the CD4% and CD4:CD8 ratio are also sometimes useful.

This Q&A include information about these cels and about interpreting the test results.

CD4 cells are a type of blood cell that is part of your immune system. They are a type of white blood cell (lymphocyte). CD4 cells are sometimes called T-helper cells or T-cells

There are two main types of T-cells.

  1. CD4 cells, also called T4 cells, are “helper” cells. They lead the attack against infections.
  2. CD8 cells, (T8 cells), are “suppressor” cells that complete the immune response. CD8+ cells can also be “killer” cells that kill cancer cells and other cells that are infected by a virus.

CD4 and CD8 counts

The normal ranges for CD4 and CD8 counts vary depending on the lab and test. On average, the normal CD4 range for an HIV negative person is between 460 and 1600. This is an average. Anywhere in this range is good.

Although generally a higher CD4 is good, an HIV negative person with a normal CD4 count of 1200 is not more healthy than someone whose normal count is 400.

The exact CD4 count is not so important. CD4 counts can vary from day to day and even from hour to hour. So the general CD4 result is more important than the exact number.

A normal CD8 range is from 150 to 1000. This test is not used as much but the results come together. It is more important to know your CD4 count than your CD8 count.

CD4 percentage (CD4%)

If you get a CD4 count that is ever unexpectedly high or low, then your CD4% (CD4 percentage) can show whether this is a real change in immune function. The CD4% is a more stable marker than the absolute CD4 count.

The CD4 percentage refers to percentage of total lymphocytes that are CD4 cells. If your test reports CD4% = 34%, that means that 34% of your lymphocytes are CD4 cells.

The average normal CD4% for HIV negative adults is about 40%. However, as with CD4 counts and other test, the range for a “normal” result in an HIV negative person is also wide – from about 25% to 65%.

CD4:CD8 ratio

The CD4:CD8 ratio is also sometimes used, but less often. This is a measure of how balanced your immune function is. This calculated by dividing the CD4 result by the CD8 result.

In HIV negative people, the normal range for the CD4:CD8 ratio is between 0.9 and 1.9. This means that there are about 1 to 2 CD4 cells for every CD8 cell.

When not on HIV treatment, just like the CD4 count and CD4%, the CD4:8 ratio drops over time. Eventually, unless you start treatment, there will be more CD8 cells than CD4 cells (i.e. the ratio drops to less than 1.0).

The CD4:CD8 ratio might be better at predicting future risk in people whose CD4 count is high (above 500 cells/mm3). However, not all studies agree on this.

Other studies have shown that starting ART soon after HIV infection has a much higher chance of keeping the CD4:CD8 ratio higher than 1.0.

Note: this answer was last updated in January 2018 from a post that was originally published in December 2006.


  1. Lisa Thorley

    Hi Reenu,

    Is this a new diagnoses? If it is then a CD4 of 404 is fine. With ARVs it will rise.

  2. Reenu

    I am positive and these are my results. Are these bad? should I be worried?

    CD4 count is 404
    CD8 count 593
    CD4/CD8 ratio is 0.68

    Thank you

  3. Simon Collins

    Hi Robindra, I am sorry but we don’t answer questions about HIV testing. This is becasue we have already posted lots on info online that answers all your questions. Please see this link:
    The 4th generation test result is very accurate. You can’t use other results for guessing your HIV status, your CD4:CD8 ration is not important at all.

  4. Robindra

    Five 4th generation tests HIV tests negative after 16 months, however CD4/CD8 ratio is falling. It measured 0.93 after one year and is 0.78 after 16 months.
    Worried a lot. Some non healing fungal infection is going on since one year.
    Please opine.

  5. Lisa Thorley

    Hi Iita,

    Your partners CD4 is very low, he’s going to need specialist care. He’ll has lost a lot of weight because is body working really hard to keep him well. Now that he’s on meds, this viral load will decrease and his CD4 will rise. As to long how it will take for his CD4 to rise, it’s not possible to say, it will however rise. As his body gets stronger his weight should improve.

    With regards to travel, this should be OK. However the best thing to do is to talk to his doctor.

    The important thing now is that he takes his meds and any other medication that he’s been prescribed.

  6. lita


    my partner was diagnozed hiv + a week ago.
    his cd count is 36 and admitted 3 times to hospital due to stomach issue.

    Doctor gave him ARV (not sure what tupe of ARV but the white table shown LA75) and cotrimoxazole (to stop bacterial infection).

    The symptoms he has now are weakness and weight loss ( more than 10%) .

    My question is, how long will it take for CD4 to increase?

    is it safe for him to travel with a bus (around 7hours) ? he said he is feeling ok now

  7. Lisa Thorley

    Hi Gino,

    Once you start taking ARVs your viral load will drop and in time your CD4 count will start to rise, there’s info about this here: https://i-base.info/guides/starting Though a CD4 of 254 is low, they go much lower, so try not to panic, as long as you’re on meds you’ll be fine. Have you been given any other medication?

  8. Gino

    I Just received the final test results after.being.diagnised.HIV pisitive: CD4 254/CD8 865. Will begin Treatment in.two days. Are.these numbers bad, and what should I expect after starting treatment? How quuckly does the CD4 cell count go up if theedication regimen works?

  9. Roy Trevelion

    Hi Tyneisha,

    A ‘normal’ CD4 count for an HIV positive person means getting above 500 on HIV treatment (ART). Please see this link for more info.

    So it looks like your ART meds (ARVs) are working well. What ARVs are you taking? And do you know your viral load result?

    Please let us know.

  10. Tyneisha

    How high and low ur CD4 has to be mine four months ago 499 now is pending


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