Is there baptism in Islam?

No, there is no baptism in Islam. Islam teaches that every baby is born pure, so there is no original sin to wash away. A person becomes Muslim by saying the shahada sincerely, with no water ritual needed, though many scholars recommend a bath (ghusl) afterwards.

Born pure, not born in sin

In Christianity, baptism is linked to washing away original sin and entering the Church. Islam doesn't share that starting point. Adam and Eve slipped, repented and were forgiven, and no one inherits another person's sin. The Prophet ﷺ said every child is born on the fitrah, the natural inclination towards God (Sahih al-Bukhari 1385). So Muslim babies aren't baptised or christened. Instead, parents whisper the adhan, give a good name, shave the baby's hair and may offer an aqiqah (a thanksgiving sacrifice).

"The colour of Allah"

Interestingly, many classical commentators linked this verse to the Christian practice of baptism with dyed water. Islam's answer is that true "colouring" is faith itself:

صِبْغَةَ ٱللَّهِ ۖ وَمَنْ أَحْسَنُ مِنَ ٱللَّهِ صِبْغَةً ۖ وَنَحْنُ لَهُۥ عَـٰبِدُونَ "[And say, 'Ours is] the religion of Allah. And who is better than Allah in [ordaining] religion? And we are worshippers of Him.'" Quran 2:138

The Arabic word sibghah literally means dye or colour: a life coloured by worship of Allah.

How you enter Islam instead

Becoming Muslim is simple: you believe and say, "I bear witness that there is no god but Allah, and I bear witness that Muhammad is the Messenger of Allah." Witnesses are nice for community support and paperwork, but they aren't a condition. See How do I take my shahada?

And the shahada does what many people hope baptism does: it wipes the slate clean. The Prophet ﷺ told Amr ibn al-As that Islam erases whatever came before it (Sahih Muslim 121).

The bath after shahada

When Qays ibn Asim accepted Islam, the Prophet ﷺ told him to take a bath with water and lote-tree leaves (Sunan Abi Dawud 355). Based on this, most scholars say a ghusl after converting is recommended, and some (in the Hanbali school, for example) say it is required. Either way, it's a practical wash for purity before prayer, not a sacrament, and nobody pours water on you. See Do I have to shower after taking my shahada?

What about my old baptism?

If you were baptised as a child, you don't need to "undo" it. It has no effect on your Islam. Muslims also respect John the Baptist as the prophet Yahya. See Do Muslims believe in John the Baptist?

Key points

Islam has no baptism because there is no original sin.
Every child is born on the fitrah, pure and inclined to God.
You enter Islam by sincerely saying the shahada.
A ghusl after converting is recommended (some say required), but it's not a sacrament.

Tip: Take your ghusl at home before or right after your shahada so you can pray your first prayer straight away. A normal shower with the right intention is enough.