Block top - The block number and size in the blockchain (in blocks) on generation of the present block Nonce - The transaction number for your from address (bear in mind this begins at 0 so a nonce of 100 would really be the 101st transaction submitted by this account) https://bookmarkcolumn.com/story20066126/new-step-by-step-map-for-blockchain-explorer-unconfirmed-transaction-https-www-hulkshare-com-circledrop4