This is an updated comprehensive list of the many Terraria mods that /tg/ (Terraria General) says are worth checking out. (Last modified: Feb 2019)
Mods in each category are roughly arranged from most to least preferable, top to bottom, except for the newest things which are pretty much all added to the bottom because lazy reasons.


• • • Mods made by people from the general - they need to be at the top for attention:

• Ammobox+
Adds a gorillion new types of ammo with a bunch of different (and unique enough) effects. A necessity for ranged runs. It also makes bosses drop ammo boxes which contain random kinds of ammunition, so you can kind of preview what they look like before batch crafting them. Rockets don't play together very well with modded rocket launchers, so be careful.

• ItemMagnet+
Adds a magnet that extends your item pick-up range as expected of a magnet mod. The range increases as you progress through the game, from a few spaces in front of you early on to well beyond the entire screen after Moonman. Extremely configurable, you can even disable this range increase thing if you find that too OP in the mod's config.

• Assorted Crazy Things
Adds a fuckton of things, namely cute slimegirls that can be kept as pets and dressed up a bit. Also adds weapons, accessories enemies, a unique dungeon miniboss and a lot more. You might find yourself having a bug-catching net (or its improved version added by the mod) on your inventory at all times.


• • • Good additional-content mods - Mods that add lots of new content to the game:

• Thorium
Adds loads of items, 2 new classes, 1 biome, several bosses, and new NPCs. Unless something better comes along in the distant future, this is the golden standard that all content mods should strive for. Yes, you can play the healer class in single player by using armor and accessories that boost radiant damage and self-healing. Bards can be played in single player to an even greater degree. Buffs from bard weapons apply to you too, not just allies.

• Fargo's Mod + Fargo's Souls
Adds a few NPCs that allow the purchasing of boss summoning items, event summoning items, and most types of wood. This also adds several dozen accessories, which got split off into a separate mod recently in order to please the people who aren't too fond of them. Many of them range from slightly OP to very OP, but are kind of, sort of balanced by the insanely long grinds (days/weeks for most of the slightly OP ones, weeks/over a month for all of the truly OP ones) you have to carry out to obtain them. Also changes a few vanilla things as of the most recent updates, such as removing the Angler's timer and letting you toggle seasonal events, so be aware of that if you prefer a close-to-vanilla experience.

• Unusacie's Battle Rods
Adds over 50 items, mostly weapons and accessories, that are based around using special fishing rods as weapons. Cast multiple lures simultaneously (up to 38 in the endgame) and take advantage of new items to make fishing fun ᵃᶰᵈ ᵒᵛᵉʳᵖᵒʷᵉʳᵉᵈ. A good way to make Calamity runs enjoyable (to a certain extent).

• Spirit
Adds more items, a new ocean event, 1 mini-biome, several NPCs, and several bosses. It's okay, but expect less content, more bugs, and significantly more item bloat in your inventory than you get from Thorium. It's also fucking dead RIP

• Chad's Furniture
Adds over 600 furniture items. Fucking Chad.

• GRealm
The usual content mod with a whole bunch of items and stuff you'd expect. Namely, adds a pre-hardmode version of Plantera and a zombie invasion event, which gets more content very frequently as you progress through the game and has tons of mod compatibility. Also adds life crystals to boss treasure bags in case you're feeling too lazy to hunt for them.

• Enigma
More items etc etc. Its biggest features are some sort of solidified potions that can be worn as accessories and combined, JoJo references, a biome that generates as the dead center of the world and is full of annoying enemies, a bunch of bosses including a literal steam train, and a "new dimension" you get warped to after killing one of those bosses, which leads to alternate versions of vanilla bosses with vastly increased stats (kill the same boss and the world goes back to normal). Feels kind of unpolished.


• • • Smaller content mods - Mods that don't obviously don't have as much content as the ones above, but are highly recommended due to having features that make the game more interesting:

• Magic Storage
Connected storage containers for simple item management. Includes a search feature to quickly find items in storage units, allows players to craft items inside the storage units without having to find and withdraw the items needed to craft them one by one, and allows up to 10 of any crafting furniture items (work benches, furnaces, etc.) to be integrated into the aforementioned crafting interface.

• WeaponOut
Held weapons are shown on your player, adds tents for temporary spawnpoints, several weapon types like whips, more shields, and support items. Also adds fist weapons which make melee objectively fun.

• Banner Bonanza
Lets you craft an item that holds any banners you put in it, while also giving you the buffs from said banners at the same time.

• Clear Events
Useful if you're the kind of person who likes to build but doesn't want to deal with events like Blood Moons or Goblins. (No forum post, only in the mod browser!)

• Teleporters unchained
Adds wireless teleporters. One big drawback is that they're only craftable post-Plantera, using ectoplasm.

• Wireless
Adds wireless transmitter and receivers (which can be combined), very useful in conjunction with teleporters if you don't want to install the above mod.

• JPAN's Bags of Holding mod
Adds craftable, reforgeable bags that can hold and automatically pick up specific items. For example, the wood bag automatically stores wood and acorns if it's equipped in an accessory slot. Bags can be crafted together to hold a wider variety of items, culminating in a bag that will automatically store any stackable items you pick up. The only downside is that there's no interface. To retrieve items you must left click a bag, move your mouse outside of your inventory, and left click again to dump all of its items into your inventory at once. Can be set to work from your inventory in the mod's own config if you don't want to waste precious accessory slots.

• Old One's Forgery
Old One's Army items (and medals) can be bought from a NPC that spawns once you have Defender Medals in your inventory. Also allows crafting summons for the event's bosses, and makes Eternia Crystals have so much HP that you're going to die of old age (and lag) before any tier of the event fails, meaning you won't need to spend much effort making sentry rods usable outside of the event.

• Portable Storage
Adds bags that essentially work like all those backpack mods from Minecraft, which means you have more inventory space. Also adds ender chests and ender bags, if you're familiar with the aforementioned backpacks you should know what this means.

• MechTransfer
Lets you transfer items between inventories so you can have some sort of item automation in the game and pretend you're playing Minecraft. Works wonderfully with Portable Storage and even more wonderfully with Magic Storage.

• Equippable Lanterns
Adds 4 equippable lanterns that work like the mining helmet, but don't take up the helmet slot so you can actually equip your main armor set. Provides better perks in hardmode.

• Summoner's Association
Adds three new items to make summoners more viable and fun to play as.

• Wormholes
Adds rarely spawning wormholes that teleport you to a random location on the map. You'll always spawn in a spot that won't kill you immediately, e.g. not on spikes, not on hellstone, not inside solid blocks, etc. Except for when you're using Calamity and it warps you to the Abyss biome, causing a giant fuck-off worm to spawn and insta-gib you.

• Vending Machines
Craft vending machines out of murdered NPCs for more convenient shops.

• Loot Bags
Enemies drop loot bags that give random items with tiers of loot depending on current progression. Pretty overpowered.

• Expeditions
A quest system for your world that grants rewards for completion, adding one new NPC in the process.

• Prefixes for Enemies
Adds prefixes (and later on, suffixes) to enemies, such as "Hardened Small Slow Zombie" among others. Applies to bosses as well. If you're familiar with the concept of champion monsters you might have an idea of what to expect.

• Enemy Affixes
Basically the same thing as Prefixes for Enemies, but focuses more on changing their stats than giving them special effects. Doesn't work very well together with PfE.

• Terraria Overhaul
Adds rolling, edge-climbing, fire spreading, better and juicier gore, and a few more things that make Terraria a bit more "crunchy", I guess. Most mechanics (like fire spread and item durability) can be disabled in the configs. Basically changes the game a lot and isn't compatible with everything, so your mileage may vary.

• Kalciphoz's RPG Mod
Gives the game some sort of Diablo feel, with enemies that have randomly-generated effects dropping randomly-generated loot as you slot gems into items and upgrade things for better effect. Be wary of exploding zombies.

• Leveled
Goes for a more standard RPG approach by focusing on levels and unlocking abilities as you go. Also changes pretty much every formula in the game and kind of forces a specific progression, so it changes the game a lot. Only really compatible with Thorium, enemies from other mods will be extremely underleveled in most cases.

• Experience and Classes
Goes for an entirely different approach and adds class-based accessories that level up, instead of your player. Gets very powerful later on.

• Solutions Mod
Adds more clentaminator solutions, as well as new mechanics for the clentaminator.

• Just Another Alchemist NPC
The mod's filename is "AlcNPCButGood" and that's pretty much what it is, basically a better version of AlchemistNPC that offers only a potion shop and lets you customize the price of every item in its config. Useful in case you want to be lazy about potions.

• Ocram 'n Stuff
Ports Ocram and its related content to the PC version. It's another boss to fight I guess, nothing to write home about.

• Ophiopod
A smaller /tg/-created mod, adds a weird worm boss that drops all kinds of hardmode souls to make grinding less painful.

• Not Enough Flamethrowers
Adds more flamethrowers, including pre-hardmode. Hooray for more options.

• Miscellania
Bunch of random things (which can all be disabled in the mod's config), most importantly an automatic fisher and an item vacuum for basic automation.

• Box of Gadgets
More random things, with the biggest ones being a way to apply prefixes before the Goblin Tinkerer (still at random), shovels to dig through dirt more quickly, and a machine that lets you choose a few particular prefixes and spends all your money trying to get them for you.

• Dye Hard
Adds a gorillion new dyes.

• Builder's Toolbox
A bunch of stuff to make building more convenient, focused on scaffolding which can be made in droves from wood and can be placed very quickly, and as you progress through the game, you get access to better ways to interact with them. There's also the Wonder Hammer after you beat the mech bosses, which is basically a wonderful hammer.

• Crystillium
Adds an underground crystal biome with its own enemies and weapons and a late-game boss with well-made sprites. Very shiny.


• • • Quality of life mods - mods that offer little or no actual content, but improve the game overall:

• Where's My Items
Let's you search nearby chests for items. Basically a much, much lighter version of Magic Storage.

• Recipe Browser
Makes the guide nearly useless by letting you search for any item and view any crafting recipe at any time.

• Instant Respawn
Does what it says.

• Shorter Respawn Time
A less cheat-y version of Instant Respawn.

• MaxStackPlus
Sets the max item limit on most items to 9999.

• Better Buffs
Adds three significant improvements to the buff system. This doesn't make buffs more powerful; they're just quality of life changes, like left clicking a buff icon to start automatically re-applying it as it runs out.

• Player Resource Bars
Adds HP and mana bars under your characters, as well as meters for potion cooldown, breath and lava resistance and makes enemy HP bars more comprehensible too.

• Yet Another Boss Healthbar
Shows health of bosses and event progress like the Goblin Army and slime rain on the bottom of the screen.

• Boss Checklist
Checklist for all the bosses (modded ones included). Includes instructions for how to summon each boss.

• Auto Trash
Place a block or item in the special autotrash slot to automatically destroy them as you pick them up.

• No More Tombs
Characters will no longer drop tombs on death.

• imkSushi's Mod
Rare accessories, weapons, and other items that may not spawn in a world such as lava charms, certain dungeon chest weapons, etc. become craftable with tokens that are dropped by enemies based on the game progression or location. Due to the amount of inventory bloat, it's highly recommended to use JPAN's Bags of Holding Mod in conjunction with it and making a Coin Bag ASAP. Also lets you "sidegrade" items, e.g. craft adamantite into titanium, craft crimson accessories into corruption accessories, craft gold into platinum, and so on, as well as potions for spawning meteorites, warp back to where you last died, and other QoL stuff.

• imkSushi's Mod - Old Recipes Enabler (You must also install imkSushi's Mod.)
Skips the tokens and lets you directly craft items with common materials.

• Helpful Hotkeys
Adds more hotkeys for things like cycling ammo, auto torches, using a mirror or recall potion and so on.

• Which Mod is This From?
Show's what mod the item is from in the tooltip.

• VeinMiner
Hold the hotkey, mine one ore, and watch as all identical ores touching it break instantly. Dirt, stone, etc. are off by default but can be configured to be vein-destroyable.

• No Text Pulse
Makes ingame text on longer have the annoying pulsing color effect.

• Item Stats+
Improved item tooltips, pretty customizable with an in-game command.

• Colored Damage Types
Does what it implies, making the damage numbers colored to match specific damage types. (e.g. melee damage uses red numbers, magic damage uses blue numbers, etc.)

• Terracustom
Customize the way your world is generated, from ore vein frequency and sizes to completely removing biomes.

• Large World Enabler
Lets you make worlds that are 2x the size of a vanilla large world. (Works with Terracustom.)

• WorldGen Previewer
Lets you see the world while it's being created. Never again waste hours exploring worlds only to see that a chunk of corruption spawned in the middle of your jungle.

• Wing Slot
Adds a dedicated wing slot to free up one accessory slot.

• MoreAccessories+
Gives Plantera a 10% chance to drop an item that gives you one additional accessory slot (once).

• Antisocial
Makes vanity accessory slots work just like normal slots. Extremely cheaty.

• Visual Radar
Makes the radar item useful by displaying a very small icon for each nearby mob on the center of the screen, showing you exactly which direction each one is in and how close they are. Doesn't create any visual clutter, except a little during invasions. Also shows bound NPCs, saving you from an early stress-related death.

• Dual Wielding
Lets you dual-wield weapons to slightly reduced effectiveness. Can be configured to disable the downsides with an in-game command.

• Better Yoyos
Gives yoyos special effects similar to what the Terrarian has.

• Wood Armor Bonuses
Makes all types of wood armor worth using in the very early game, and arguably pearlwood too in early hardmode.

• Item Checklist
A checklist of every item you've picked up/crafted, can be filtered and searched so it can be useful on runs where you intend to get all items of a specific damage type or such.

• /tg/ mod
Adds factions (Elves and Dwarves) that have special buffs/debuffs when at certain heights/depths, adds gimmicks that each player gets special debuffs when in certain conditions (e.g. "Vampire" lights you on fire when in sunlight). Only really possible in multiplayer, since trading between factions is highly recommended due to the depth-related debuffs for each faction. I'm pretty sure it's dead but it's in the list anyway.

• /tg/ Waifus
Adds a pet Nurse that drops hearts.

• Googly Eyes
Adds googly eyes to bosses. Not so evil now, are they?

• Unleveled
Adds a few options to change your HP/Mana bars, as well as the damage effects and adds a critical HP sound.

• Omniswing
Allows any weapon to be auto-fired, similar to items like the Muramasa. Not very useful if you're using WeaponOut, as it has an item that offers the same function.

• HERO'S Mod
Lets you cheat in single player. This is useful for things like changing or locking the time of day or weather, summoning bosses, spawning items, etc. It allows you to do pretty much everything.

• Cheat Sheet
Also lets you cheat in single player, a bit less than Hero's mod.

• Luiafk
Jack-of-all-trades mod centered on infinite ammo and potions (in fact, it makes them infinite if you have large enough stacks of them by using MaxStacks+ or similar). Has a bunch of great features like an infinite painting kit, an automatic wall placer, and automatic herb/tree harvesting, but due to the whole infinite resources thing, how it also adds its own combinable potions that result in all buffs without using a buff slot, and how none of the mod's features can be disabled, it's not a mod for everyone.

• Census
Shows what are all the available town NPCs, and what are their spawning conditions. Useful for planning your commieblocks on large modpacks.

• Angler Shop
Replaces Angler rewards with tokens that can be spent to buy exactly which rewards you want. Basically how that faggot NPC should always have been.

• Dye Easy
Makes dye materials be crafted into three dye items instead of just one.

• Non-reset Timer
Adds timers that don't get reset when you leave the world. What the fuck were they thinking?

• Buffed damage over time debuffs
Instead of a few irrelevant damage points per tick, makes debuffs get based on their target's total health, greatly increasing the effectiveness of even the on fire debuff.

• WeaponOut Lite
In case you don't want WeaponOut's content but you still want to see your character holding your weapons.

• Start with Base
Checks how many town NPCs you have and generates a huge base on spawn with just enough rooms to accomodate them all, as well as giving you space for your chests and such. Basically an automatic commieblock maker for people who are too lazy to make commieblocks. Has a bunch of customization options, but you'll need to either check the Terraria forum thread to understand how they work, disable Worldgen Preview to be able to mess with them in-game, or enjoy a beautiful house made of hay.


• • • Not recommended mods - Only a masochist or a teenager with no frame of reference for what makes games good or bad would consider playing these mods. You've been warned.

• Calamity
Balancing is rough, pre-hardmode is okay, but after that it just overshadows vanilla/other content mods. Bosses can be difficult as all fuck, with acid rain endlessly falling once Moonlord is beaten. Dev had a sperg moment and fucked off to his Discord bubble when people on the forums criticized the mod and his mod's terrible balancing. It's more about quantity over quality. This one's best used on its own. Also pretty incompatible with a bunch other mods due to how it changes the world's size in order to accomodate planetoids above the space layer (a good idea with awful execution - pretty much the mod in a nutshell). Consider using the CalamityNerf mod in case you still want to go with it, as that mod tones down everything Calamity adds to slightly less dumb values.

• Tremor
A fuckload of half-baked ideas crammed into a single mod that's just terrible overall. Some content—the fidget spinner yoyo from Calamity, the Ugandan Knuckles item from alchemistNPC, and so on—is even stolen from other mods. (From those item names alone, are you starting to get an idea of what the terrible mods in this category are like?) The devs of this one eventually fucked up so badly that they split apart and work on other things now.

• Joost
Has most of the same problems as Tremor, aside from Joost's devs not stealing any content. If not for it having memes that appeal to autistic children, nobody would even know this god-awful mod exists. Now also adds weapon/accessory prefixes that might make the game even easier. On the other hand, it has some genuinely good content such as a swinging hook and a cannon that makes (un)building faster.

• Sacred Tools
Most of the same problems as the mods above: poor balance, too many bugs, too many outdated, cringey memes, cringey NPC dialogue, etc. Like every other mod in this category, this is yet another one made by children, for children.

• Antiaris
Fantastic sprites that look out of place in Terraria are the mod's only arguably good point. It has many of the usual problems.

• AlchemistNPC/Lite
Lets you buy potions a NPC, that much would be okay enough if not for the fact that it also adds a bunch other NPCs that sell all kinds of materials, charms that make your potions don't even get consumed or reforging always yield the best results, and in the original mod's case, literal meme weapons that are so bad the author felt forced to create a "Lite" version of the mod because people couldn't stop complaining. Seems to be getting slightly more balanced as of recently enough by merely making all potions rather expensive, but it's still something that you should only care about if you're feeling very lazy (and even then, consider using Just Another Alchemist NPC instead).

• Reduced Grinding
Reduces grinding... way too much. When you get an average of 10 Rods of Discord every underground Hallow trip, you know that something got fucked up somewhere. It might be very configurable, but given the default values and how at that point there's no reason to even have a reduced grinding mod in first place it's better to just not bother with it. Fargo's Mod lets you craft grind-heavy items using enemy banners anyway.

• Most of the "my first mod" mods and "so-and-so's weapons"
A lot of these are good to avoid unless you want to just mess around. They're mostly just things made by those new to modding. They're not all bad, but a lot of them are just OP weapons or babby's first ore.

• • •

Most, if not all, of these mods should work together (unless specified).
It's best to not use all of them at the same time however as you'll likely be overwhelmed with content or there could be the chance something breaks. Do take note: The more mods you enable, the more memory you'll use up, which isn't a problem for the beefier PCs but for you toasters out there, take that into consideration.

Beginners to modded Terraria may wish to pick several quality of life mods, and somewhere around zero, one, or two of the good additional-content mods, such as Thorium.