Are all my sins forgiven when I become Muslim?

The proof, in short

The Quran says it directly:

When a man named Amr ibn al-As came to accept Islam, he asked for one condition: that his past sins be forgiven. The Prophet Muhammad ﷺ told him: "Do you not know that Islam wipes out what came before it?" (Sahih Muslim 121).

Another companion, Hakim ibn Hizam, asked about the charity he had given before Islam. He was told: "You accepted Islam along with all the good you did before" (Sahih al-Bukhari 1436, Sahih Muslim 123).

More than a clean slate

The Quran goes further. For people who repent, believe and do good, "Allah will replace their bad deeds with good ones" (Quran 25:70). Many scholars explain that sincere change can turn your past into a source of reward, not shame.

What you don't need to do

• Confess your past to anyone. Islam has no confession to a priest or imam. Your past is between you and Allah, and it's better to keep it private.
• Make up old prayers or fasts. They weren't required of you before Islam.
• Remove old tattoos. Most scholars say you don't have to, especially if removal is painful or expensive.
• Retake your Shahada because of something you did years ago.

What still carries over

Forgiveness covers your relationship with Allah. What you owe to people is a separate matter.

• Debts and loans still need to be repaid.
• If you took something that belongs to someone, return it or its value if you reasonably can.
• Legal duties, like child support, contracts or court fines, stay in place.

"But I still feel guilty"

That's very common among new Muslims. Guilt that pushes you to do better is healthy. Guilt that makes you feel you're "not a real Muslim" doesn't come from Islam.

And from now on? You'll still make mistakes, like everyone. Each time, say "Astaghfirullah" (I seek Allah's forgiveness), mean it, and try again. The door of repentance stays open.