1. Data type for fields in Access
By Mark Gillan

2. Number types – field size

3. Data Type Description Storage Size Common Use Byte
Decimal
Precision
Storage
Size
Common Use
Byte
Numbers ranging from 0 to 255
None
1 byte
An alternative to Yes or No, True (1) or False (0) and integer within range – no decimal point or fractions
Integer
Numbers ranging from -32,768 to +32,767
2 bytes
Whole numbers – doesn’t include a decimal point, restricted to range
Long Integer
Numbers ranging from minus (negative) 2,147,483,648 to plus (positive) 2,147,483,647
4 bytes
Whole numbers – doesn’t include a decimal point. DEFAULT number type.
TIP: Use when creating a foreign key to relate a field to another table Autonumber primary key
Single
For numeric floating point values from
Negative -3.4 x 1038 to Positive +3.4 x 1038 7
Large floating numbers for scientific notational purposes – limited precision
Double
Negative x to Positive x 10308 15
8 bytes
Double the storage capacity of single / float as above. Limited prevision
Replication ID
For storing Globally Unique Identifier (GUID) that is required for replication
N/A
16 bytes
NOTE: Replication is not supported by the .accdb file format
Exact numeric value with amount of digits to the left and the right of a decimal point. 28
12 bytes
Can have fractional parts