RLP Tests

Describes an RLP (https://github.com/ethereum/wiki/wiki/RLP) encoding using the .json file.

Location /RLPTests
Supported Hardforks Hardfork-independent
Status Actively supported

Test Implementation

The client should read the rlp byte stream, decode and check whether the contents match its json representation. Then it should try do it reverse - encode json rlp representation into rlp byte stream and check whether it matches the given rlp byte stream.

If it is an invalid RLP byte stream in the test, then ‘in’ field would contain string INVALID.

Some RLP byte streams are expected to be generated by fuzz test suite. For those examples ‘in’ field would contain string VALID as it means that rlp should be easily decoded.

Note that RLP tests are testing a single RLP object encoding and not a stream of RLP objects in one array.

Test Structure

   "rlpTest": {
        "in": "dog",
        "out": "83646f67"

   "multilist": {
        "in": [ "zw", [ 4 ], 1 ],
        "out": "c6827a77c10401"

   "validRLP": {
        "in": "VALID",
        "out": "c7c0c1c0c3c0c1c0"

   "invalidRLP": {
        "in": "INVALID",
        "out": "bf0f000000000000021111"


  • in - json object (array, int, string) representation of the rlp byte stream (*except values VALID and INVALID)
  • out - string of rlp bytes stream