# [privacytools.io](https://www.privacytools.io/) encryption against global mass surveillance #Contributing Guidelines ##Images - Provider logos should be exactly 200 x 70 ([example](https://www.privacytools.io/img/provider/AirVPN.gif)) - Tool logos should be exactly 120 x 120 ([example](https://www.privacytools.io/img/tools/ChatSecure.png)) ## Hyperlinks - Please add the `target="_blank"` attribute to links ([example](https://github.com/privacytoolsIO/privacytools.io/blob/01af55ae9d03e9bb453f7891093704aaade80ec4/index.html#L136)).