Difference between Debt to GDP ratio and fiscal deficit as a measure of GDP in percentage terms????

Dear Student
The underlying difference between these two concepts is the difference between "Debt" and "Deficit". 

• Debt refers to the total borrowings of a country at a particular point of time.
• Fiscal Deficit is the amount of borrowings that the country has to raise in this current year.

Therefore, the Debt to GDP ratio shows the cumulative debt as a percentage of GDP while Fiscal Deficit as a percentage of GDP shows the borrowings of the current year only.
Hope this information clarifies your doubts. Keep posting :-)
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