Are all block ciphers FPE (format preserving encryption)? A FPE preserves the format. There is a correspondence between the format of the ciphertext and the plaintext.

Given that a message in some binary enconded format can easily be divded in some l blocks of n bits which will be encrypted to l blocks of n bits I would call (some necessary padding issues ignored) pretty much a format preserving encryption).

Is this true? Are block ciphers considered to be FPE? 

Or are the ciphers working on blocks which have a disparity of the input->output ratio of either block numbers and block size?
The formal definition of a block cipher is a function
$$
E_K(P) := E(K, P): \{0,1\}^k \times \{0,1\}^n \rightarrow \{0,1\}^n
$$

The input and output spaces are by definition n-bit blocks, so the operation of the cipher in Electronic Code Book (ECB) mode is technically "format preserving".

That is not however what "Format Preserving Encryption" (FPE) generally refers to, nor does it mean that all block ciphers modes of operation are format preserving, nor that all symmetric encryption functions are format preserving.

NIST SP800-38G, which recommends FPE modes of operation for block ciphers, defines FPE as "Given any finite set of symbols, like the decimal numerals, FPE transforms data that is formatted as a sequence of the symbols in such a way that the encrypted form of the data has the same format and length as the original data."  In other words FPE is a function

$$
E_K(P) := E(K, P): K \times M \rightarrow M
$$

where M is not necessarily a block of bits.  For example M could be a 16-digit credit card number, or a Social Security Number.  The ciphertext - rather than being a block of bits - will have the same size and alphabet as the input; that is it will look like a credit card number or SSN.

A typical use of FPE is to selectively add data encryption to fields within legacy messages without modifying the message format or the validation functions of your legacy systems.  

Many block cipher modes of operation cause ciphertext expansion - where the ciphertext is larger that the plaintext - are are not format preserving. Any mode that includes a checksum or requires a message-unique Initialisation Vector (IV) will cause ciphertext expansion.