Plants vs. Zombies Web Version is a free version of the game available at the PopCap Games official website. There are three modes: Adventure Mode, Survival and Puzzle. In the Adventure Mode of this version the player can only progress until they finish level 2-4 before they must start again as a new player. However, if one unlocked the Survival and Puzzle modes on one computer previously, they will be able to continue playing those modes. Survival Mode on the web version is a modified version of Survival: Endless which takes place during the night, and the player may only choose four plants at a time. Puzzle Mode consists of a modified version of Vasebreaker. The player's progress will be lost on the Survival and Puzzle modes if they quit, unlike the full version.
- Cherry Bomb
- Snow Pea
- Grave Buster
There are eight zombies in the Web version.
- Flag Zombie
- Conehead Zombie
- Buckethead Zombie
- Pole Vaulting Zombie
- Newspaper Zombie
- Screen Door Zombie
- Giga-Football Zombie
This is a unique version of Survival: Endless only available for this version. It has quite unique features, such as not being available to select more than four plants, limited kinds of plants available, and the Giga-Football Zombie. The Giga-Football zombie takes same amounts of damage as the Gargantuar (150 normal damage shots), but is fast as the Football Zombie. The presence of this zombie as well the large mass of zombies appearing (about 400 Giga-Football Zombies until level 15, about 3000 in total) makes this level extremely hard, being virtually impossible to get past wave 20. Chompers can devour the Giga-Football Zombie in one bite, which is a recommended way to combat it as it cannot be killed by one instant kill.
- The zombies in the online version will usually have no bone seen upon losing their arm.
- There is a Survival: Night (Endless) here, because if it took place at daytime, mushrooms would not be able to wake up, since the player never gets the Coffee Bean.
- The zombies will not attempt to eat the instant kills (except Chomper), similar to Plants vs. Zombies 2.
- There are two glitches with the Newspaper Zombie: when falling to die, a bone in his arm will appear, and his eyes will flash angry for no reason.
- The modes are on different buttons, unlike the full version.
- Maybe the order of buttons is intentionally changed because there is no Mini-games mode in the Web version.
- If the player beats the game, the plants will reset, so they cannot use mushrooms during the day.
- Instead of the Potato Mine the player will get the Squash.
- One can see the silhouettes of the Ice-shroom, Doom-shroom, Lily Pad, Potato Mine, Threepeater, Tangle Kelp, Jalapeno, Spikeweed, Torchwood, Tall-nut, Cactus and Blover when the player has unlocked all the Online Plants.
- The Snow Pea makes a different sound effect when it shoots frozen peas on the online version than it normally does (a "jingle bell"-like sound effect).
- The seed packets are much bigger in this version.
- There is no shadow below the plants or zombies.
- If the player puts their mouse over the Giga-Football Zombie it will say "Football Zombie." This is because there is no Football Zombie in this version.