Hi, i'm Zixem and i developed a few SQLi challenges.
More about SQL Injection.

Rules!

[SQLi challenges]

Level 1 (Super Easy)
Level 2 (Easy)
Level 3 (Medium)
Level 4 (Normal)
Level 7 (Medium)
Level 8 (Hard)
Level 9 (Medium)
Level 10 (Pro)

[Brute-Force challenge]
Level 5 (Get your "bot-writing" skills)

[SQLi-Blind challenges]
Level 6 (Experienced)
Using information_schema\tools in blind challenges is illegal!

ZiXeM
Update @ july 1st,2017~: Click here if you want me to teach you web security