Theoretically we can report dates as young as a single year, but the margin for error may be greater than the date reported. On the other hand, if the sample is too old, not enough C-14 may remain for an accurate measurement. This means that the upper limit of C-14 dating is currently around 50,000 years ago.
What are the limitations of c14?
The practical upper limit is about 50,000 years, because so little C-14 remains after almost 9 half-lives that it may be hard to detect and obtain an accurate reading, regardless of the size of the sample. Fourth, the ratio of C-14 to C-12 in the atmosphere is not constant.
What is the limit in using carbon 14 as a measure to determine a fossils age?
about 50,000 years The short half-life of carbon-14 means its cannot be used to date extremely old fossils. Levels of carbon-14 become difficult to measure and compare after about 50,000 years (between 8 and 9 half lives; where 1% of the original carbon-14 remains undecayed).