As a number of other bloggers have already mentioned, the NA28 – that is, the latest critical edition of the Greek New Testament – can be read online for free. It lacks the critical apparatus indicating differences between manuscripts, and features just the eclectic text, i.e. what the committee decided was most likely to represent the original reading.
Here’s a sample of what it looks like when you copy and paste from it:
- ΚΑΤΑ ΙΩΑΝΝΗΝ
1:1 Ἐν ἀρχῇ ἦν ὁ λόγος, καὶ ὁ λόγος ἦν πρὸς τὸν θεόν, καὶ θεὸς ἦν ὁ λόγος.
2 οὗτος ἦν ἐν ἀρχῇ πρὸς τὸν θεόν.
3 πάντα δι’ αὐτοῦ ἐγένετο, καὶ χωρὶς αὐτοῦ ἐγένετο οὐδὲ ἕν. ὃ γέγονεν4 ἐν αὐτῷ ζωὴ ἦν, καὶ ἡ ζωὴ ἦν τὸ φῶς τῶν ἀνθρώπων·5 καὶ τὸ φῶς ἐν τῇ σκοτίᾳ φαίνει, καὶ ἡ σκοτία αὐτὸ οὐ κατέλαβεν.