HOI4 Navy Guide 2026: Fleet Composition and Ship Design

Everything below answers one question — how to build a navy in HOI4 that wins the sea zone you send it to — in the order the game makes you answer it: which hulls go in the water, how many screens stand in front of them, which mission each task force sits on, and where the naval experience goes. Sections 1 to 9 follow a build from the ship designer to the fleet screen. Sections 10 to 15 are the mechanics underneath it, so you can rebuild any of this after a patch instead of waiting for someone to post the new template.

🎯 The core idea

One ship wins naval combat right now: a destroyer with full light attack and torpedoes bolted on. Most "meta" multiplayer fleets are that single template copy-pasted until the dockyards run out. If you only take one thing from this page, build that destroyer and stop reading.

The rest of this exists because that template will be nerfed. Everything below — how battles resolve row by row, why screening efficiency is the only ratio that matters, which doctrines feed which hull — is the machinery that produced it. Learn the machinery and you build the next meta template yourself instead of waiting for someone to post it.

Do this first

1. Get naval dominance the cheap way, not the expensive way. The single biggest dominance modifier is the hull, not what you bolt to it. A blank carrier with no modules is the most dominance per factory in the game. A naval dominance battlecruiser gives slightly less for much less IC. Neither ship ever enters a battle — they exist to sit on a patrol mission and generate a number.
2. Fix screening before you fix damage. Three screens per capital, one capital per carrier. Below 100% screening efficiency, enemy torpedoes start reaching your capital ships, and a battleship dies to destroyers it never got to shoot at.
3. Keep recon out of the main fleet. Surface detection is averaged across every ship in the task force. The meta destroyer has 38 surface detection and drags that average into the floor, so a separate five-ship recon fleet on patrol does more for you than any amount of radar on the death stack.

1. The ship designs

All of these come off the designer screens in the source video. The author keeps the exact slot-by-slot loadouts in a linked Google Doc rather than reading them out, so treat the notes below as the shape of each design and pull exact module tiers from your own tech level.

The meta destroyer as the author builds it: light attack 13.8, torpedo attack 43.2, production cost 2418.

1. Meta destroyer freeFull light attack, then torpedoes on top. Deals the most damage to the enemy screening line of anything in the game for its cost. This is the whole meta. 12:03
2. Carrier cheapMax hangars, then max AA, radar, engines. A basic hull is fine — the advanced one is one extra slot. Never add armour: torpedoes ignore it, so it buys nothing and costs speed. 9:36
3. Battleship cheap2× AA, 2× secondary guns, heavy guns for the rest, dual purpose where it fits. Use the cheapest armour available. You will not have top-tier guns and fire control everywhere and you do not need to. 11:15
4. Heavy cruiser setup2× AA, 1× dual purpose, rest heavy guns. Normally skipped as "a worse battleship" — but there is a budget research path: research only the cruiser line and build light + heavy cruisers instead of funding battleship, destroyer and carrier tech separately. Fine against the AI. 11:20
5. Recon light cruiser setupBuilt purely for surface detection and kept in its own task force on patrol + never engage. You want about five, plus spares. 12:56
6. Escort destroyer setupDepth charges and sonar, anti-submarine only. Never in the main fleet — these sit on convoy escort. 12:40
7. Submarine grindTorpedoes and snorkels, later anechoic tiles and Walter engines (both special projects) to push visibility very low. Stack submarine MIO, national submarine bonuses and doctrine on top. Mine-laying submarines are not worth it. 13:21
8. "Roach" destroyer skipPure dodge, no damage, fast and cheap — a body to soak hits. Only if you desperately need screens right now. Real ships are better. 12:20

Every hull from the list above, together in one list of ship designs — not a production queue, which never shows more than one hull at a time.

The super heavy battleship — the one ship that justifies expensive armour.

Every design, as the designer shows it

10:04 — the carrier. Deck 100, cost 12,290, and nothing bolted on that would slow it down.

11:15 — the ordinary battleship, anti-air 33.1. The frame at 10:34 that the narration lands on is actually the super heavy above, not this.

11:08 — the naval dominance battlecruiser from the opening advice: cheap hull, never fights, exists to hold a patrol.

11:42 — heavy cruiser, heavy attack 45.0, cost 7,254.

11:53 — the recon cruiser, submarine detection 33.0, cost 3,876. There is no separate offensive light cruiser in this run; the designer returns to this same hull later.

12:47 — escort destroyer: depth charges 67.0, detection 41.2.

12:32 — the roach. Cost 780 against the meta destroyer's 2,418, and no damage to speak of.

13:42 — submarine, torpedo attack 90.0, cost 1,344.

2. How a naval battle actually resolves

This is the part that makes every ratio below make sense.

8:03 — the Battle of the North Sea with the rows laid out: screens in front, capitals behind, support and carriers at the back.

Ships line up in rows: row 1 screens, row 2 capitals, row 3 support ships and carriers, with submarines underneath. Every gun can only reach the first line — except heavy guns, which reach the first two. That is the entire reason capitals are worth their cost, and the entire reason screens exist.

Torpedoes are the exception that breaks the wall. They penetrate the screening line when enemy screening efficiency drops, or through torpedo screen penetration modifiers. At 100% enemy screening efficiency with 10% torpedo screen penetration, 10% of your torpedoes still reach their capitals. Light attack kills screens, hard attack kills capitals, and piercing below enemy armour cuts your damage — exactly like land combat.

Build past those ratios. Losses during a battle drop you below 100% screening efficiency, and that is the moment torpedoes start landing on your battleships.

3. Missions

1. Patrol — generates naval dominance 1:20
2. Strike force — capitals sit in port until an enemy is spotted 2:38
3. Convoy raiding — removes enemy dominance instead of adding yours 4:07

Assign one zone to an admiral and every task force stacks there. Assign two and they split one per zone, rotating every few weeks. Each sea zone has its own dominance requirement and enemy ships present have to be contested — a single submarine is not going to patrol the Gulf of Mexico.

Strike force is usually the right home for capitals. Instead of patrolling and generating raw dominance, they hand your patrolling ships a percentage modifier that applies across every assigned zone, burn less fuel, and stay in port where nothing can kill them.

4. Fleet composition

The best navy is your entire navy, in one task force. Once you death-stack, supply is the only thing still limiting you.

A worked multi-theatre composition, as narrated: 4 carriers : 8 battleships : 16 destroyers, ideally with super heavy battleships in the capital slots.

The composition editor on screen tells a slightly different story: it targets 4 carriers, 8 capitals and 40 destroyers — five screens per capital rather than three. Treat 3:1 as the floor and this as what the author actually builds toward.

1. Main fleet — keep in port, never repair, no automatic split off, always engage 16:33
2. Recon fleet — one recon cruiser duplicated ×5, patrol + never engage 17:00
3. Escort fleet — a few escort destroyers on convoy escort, reinforce and split-off enabled 17:08
4. Raiding fleet — ~10 submarines per task force, up to 10 task forces per admiral 17:35

Carrier overstacking has been removed. The old advice to run five carriers in a stack is dead — if you learned navy from a guide older than this patch, that is the first habit to drop.

5. Carrier planes

Aim for green air, then stop thinking about it. The rule of thumb is 50/50 naval bombers to fighters; once you hold green air shift toward more naval bombers, and if you are at red or yellow air shift toward fighters — ideally heavy fighters with the range to reach the fight.

6. Research, MIOs, doctrines, spirits

Research priorities

Smoke generators, damage control and fire control methods first — the author calls these "super important". Then the hull for whatever you are actually building, torpedo tech if you run submarines, basic depth charges, upper-tier tech for screens and lower-tier for heavy ships. Transports if you plan invasions, underway replenishment for range, snorkels for submarines. Mine warfare does not matter.

MIOs

21:50 — the shipbuilder MIOs. The types are what the table above names; the organisations themselves are nation-specific, so in this German run they read Deutsche Werke, Deschimag, Germaniawerft and HDW.

Doctrines

Fleet in Being as the grand doctrine for a normal navy — it stays good even with carriers. Trade Interdiction only if submarine raiding is genuinely all you care about and dominance is not.

Then: Patrol Boats for screens — "no discussion", because it unlocks Selective Engagement. Naval Gunfire Support for capitals, almost always. Light Task Forces for carriers unless you are running a carrier-focused fleet, in which case Mass Carrier Fleet. For submarines, Long-Range Submarines if you have the special projects, otherwise Capital.

Spirits

Instilled Aggression, hands down. Under Naval Command take Selective Engagement first; Night Fighting and Rapid Concentration are both fine after it. Under Spirit of the Navy, Naval Refit Yards, Naval Reform and Fleet Interoperability are all defensible — which one is right depends on your doctrine.

24:00 — the Spirit of the Navy panel. Worth knowing that the doctrine tree itself is never shown filled in anywhere in the video, so the picks above come from the narration rather than from a visible build.

7. Special projects

• free clearly worth the slot
• setup depends on your fleet
• skip arrives too late to matter

1. Shock hardening techniques freeArtillery soft attack across every artillery type, not just naval. Called out as "really good".
2. Super heavy battleship freeVery strong. Build it whenever the research and project allow.
3. Proximity fuse freeNaval AA attack.
4. Anechoic tiles + independent propulsion setupSubmarine visibility. Only if submarines are a real part of your plan.
5. Cruiser submarine / fleet submarine setupVery low submarine visibility, and unlocks long-range submarine tech.
6. Underway replenishment setupRange. See the comment below about what it does to your convoy pool.
7. Ice aircraft carrier skipToo late-game to matter.

8. Micro that is actually worth doing

Setting the production drop-off port per ship is the one that quietly saves runs: without it, expensive ships trickle out of whichever dockyard finished them and sail into a war zone one at a time. Point them all at a safe haven and the fleet leaves together.

A naval headquarters gives fleet-wide modifiers if you build it and assign an admiral — but it costs about as much as a civilian factory, more if you already have one.

9. Two free things almost nobody takes

26:58 — the tooltip itself, reading +1.42% on this particular set of coastal states.

10. The best destroyer template for 2026

Section 1 hands you the ship. This is the reasoning behind it, which is the half that survives a patch.

Two targeting rules do most of the work. Light guns can only fire at the closest non-empty group — in a full battle that is the enemy screening line and nothing else. Heavy guns reach the first two groups, which is the entire argument for owning capital ships at all. A destroyer built around light attack is therefore a screen-killer by construction: while the enemy has screens it cannot shoot at anything else, and while the enemy has screens there is nothing else worth shooting at.

Torpedoes are the exception, and the rule is worth memorising exactly. A torpedo's chance of targeting the enemy battle line is 100% minus their screening efficiency, and reaching the carrier group behind it needs a second check against 100% minus their carrier screening efficiency. Torpedoes therefore do nothing at all to a fleet screened at 100%, and a great deal to one that has started losing destroyers. That is the whole case for carrying both weapons on one hull: the guns pay immediately, the torpedoes pay once the guns have done their job.

The destroyer hull gives you six fixed slots and two custom ones, so the template is a budget rather than a wish list.

The other reason destroyers carry the meta is defensive. Surface visibility is a ship's profile: the higher it is, the more easily the ship is spotted outside a battle and the more easily it is hit inside one. Destroyers carry the lowest profile of any surface hull, so the same fleet budget buys you more guns and more misses.

For what the naval rework changed about which of these hulls to spam and in what quantity, that is the navy meta guide. This page stays on the templates and the mechanics under them.

Heavy cruiser vs light cruiser

The heavy cruiser vs light cruiser argument is usually had about firepower and is really about which line the ship stands in. A light cruiser is a screen; a heavy cruiser is a capital ship. Every heavy cruiser you add raises your screening bill by three destroyers, while every light cruiser pays part of that bill itself.

The guns follow the same split. Light Cruiser Batteries I–IV are light attack — roughly 4 to 7.5 per module — and can only reach the closest group. Heavy Cruiser Batteries I–IV are heavy attack with heavy piercing, roughly 6 to 12 attack and 22 to 34 piercing, and they reach the second group where the enemy capitals actually are. Both hulls share the cruiser engine and Cruiser Armor I–IV, and the heavy cruiser carries the lightest armour of any capital ship, so what a heavy cruiser buys you is reach rather than toughness.

Piercing decides whether that reach is worth paying for. Damage scales off the ratio of your piercing to their armour: at twice their armour or better you do full damage and double critical chance, and below a tenth of it you do a tenth of the damage and cannot land a critical at all. A heavy cruiser that cannot pierce what it is shooting at is a very expensive screen that does not screen.

11. Carrier build guide: what really limits your deck

Section 5 covers what to put in the air. This is what the ship underneath does to it — because the number deciding how much of your deck actually flies is sortie efficiency, and it starts at 50%.

Three things move it:

• Deck space. Overcrowding costs 2% sortie efficiency for every 1% you exceed the deck, so a wing that does not fit is worse than a wing you never built. Sortie efficiency above 100% absorbs that penalty rather than wasting the surplus, which is the only reason to push it past full.
• Screening the carrier group. 100% carrier screening efficiency is one capital ship per carrier, plus 0.25 per convoy present, and holding it is worth up to +10% sortie efficiency on top of keeping torpedoes out. The same battleships are doing two jobs at once.
• The clock. Carrier planes sortie every six hours, and they will not fly at night without the officer corps spirit that allows it. A battle joined at the wrong hour delivers fewer waves than the arithmetic promises.

Carrier fighters never target ships at all. Everything they do is protect the deck and contest the sky above it, which is why the fighter half of the wing earns its slots even in a fleet that only wants to sink things: a carrier that loses the air above it stops being a carrier and becomes a large, slow capital ship.

12. Submarine guide for 2026: hidden is the only stat that matters

A submarine guide comes down to one binary. A hidden submarine cannot be targeted at all, and depth charges — the only weapon that can hit one — work only while it is revealed. Every design decision below is about how long that revealed window stays open.

Three build consequences fall straight out of that table:

1. Visibility modules are the design. Snorkels take 7–13% off visibility depending on tier, and the reveal chance from your own torpedo attacks scales with visibility — so a quieter boat is not merely harder to find, it is harder to keep found after it shoots.
2. Engagement rules are half the ship. Submarines only attack capital ships on Medium risk or higher, and only attack screens on High risk. A wolfpack left on the cautious setting is an expensive scouting flotilla.
3. Bad positioning multiplies visibility, by up to 200%. Submarines that arrive at a battle badly positioned are the ones that get found and depth-charged.

Depth charges are worth understanding from the other side as well: base hit chance 11%, hit profile 100, which means they are equally accurate against every target regardless of how small or fast it is. Nothing else touches a submarine, and against submarines that is enough.

Convoy raiding, and what it actually pays

Most convoy raiding advice stops at "put the submarines on convoy raiding". The cost of that order is the part worth knowing: a task force raiding convoys contributes only 25% of its naval supremacy, against 100% on strike force and 75% on patrol. Raiders are not holding the sea while they raid.

Coverage is the second limit. Each raiding task force covers about 1.5 strategic regions efficiently, and a fleet asked to cover more than that loses efficiency everywhere at once — which argues for several small raiding task forces rather than one large one, and is the exact opposite of the death-stack rule that governs your fighting fleet.

Two more numbers change what supremacy you get for the ships you already own. Air superiority is worth up to +100%, making each ship count as two in a sea zone whose sky you own. Thin naval intelligence cuts the other way: at 10% naval intel efficiency or less your supremacy is halved, with the penalty shrinking to nothing by 40%. And a task force set to do not engage contributes nothing at all.

Naval invasions read the same number. You need more than 50% naval supremacy in every strategic region your divisions cross, and only for the moment the invasion launches — once it is away it continues whether or not you still hold the sea.

13. The screen to capital ship ratio, worked out

Three to one is the right answer to the screen to capital ship ratio, and it is also the floor of a formula with three more terms in it, each of which can quietly move what your fleet actually needs.

• The base. 100% screening efficiency needs three screens per capital ship and per carrier. Carriers count in that total as well as carrying their own separate requirement.
• Convoys count. Add 0.5 screens per convoy present in the battle. A fleet escorting an invasion is screening far more than its own warships.
• Carriers are screened twice. The carrier group needs one capital ship per carrier, plus 0.25 per convoy, for 100% carrier screening efficiency.
• Positioning multiplies all of it. The positioning penalty scales linearly to −50% at 0% positioning, which doubles the screens required for the same efficiency.

Run the multi-theatre fleet from section 4 through that. Four carriers and eight battleships is twelve capitals-and-carriers, so 100% screening efficiency wants 36 screens, not 16. At 16 destroyers that fleet screens at roughly 44% — which means about 56% of every enemy torpedo gets a check against your battle line instead of being stopped by your destroyers. That is where the composition editor's 40-destroyer target comes from, and it is why "build past the ratio" is not padding.

14. Naval doctrine guide: one grand branch, four tracks

The naval doctrine tree is one mutually exclusive choice followed by four independent tracks. The grand choice is the one you cannot walk back.

The four tracks run alongside it, one per hull class, and you draw from all of them:

Several of those are DLC-gated, so a tree with gaps in it is not a bug. Read the tracks against what you are actually building rather than against a tier list: the screens track is where a destroyer fleet's damage comes from, the capital ships track is where a gun line stops dying, and the carriers track is mostly wasted on a fleet with two carriers in it.

Naval experience is the real constraint on this tree, not political power. Exercises pay it out until a ship reaches Regular and burn 60% of normal fuel while they do it, so the picks that matter most are the ones you can afford before your first real battle.

15. The nation you pick, and the treaty that caps its ships

Which is the best navy nation in 2026 is really two questions: who starts with a fleet, and who can build one. The United States begins the 1936 scenario with 229 vessels, weighted toward submarines rather than heavy hulls, and the industry to replace whatever it loses. The United Kingdom starts with the fleet everyone else's treaty ratios are measured against. Japan starts with carriers already in the water, which is the one hull that takes longest to grow from nothing. Germany — which is what most of the designs in this guide are built as — starts with almost nothing, and is the honest place to learn, because every hull in the water is one you chose.

For five of those countries the catch is the London Naval Treaty, which binds the United States, the United Kingdom, France, Italy and Japan, and caps what they may put in the water:

Signatories also hold their capital ship count in ratio to the United Kingdom's. Leaving early costs political power — 25 for a fascist country, 150 for anyone else — and the treaty lapses on its own once any two major powers are at war or world tension reaches 75%. The practical reading is that a treaty navy's first years are research and dockyard years rather than super-heavy-battleship years, while a country with no treaty and no fleet can start building the templates above the moment the research lands.

From the comments

Where to go next

Fleet composition is only half the problem — the other half is which nation you are building it for. The Japan guide runs a naval-led campaign end to end and shows the doctrine and dockyard order that pays for it, while the UK guide and the USA guide cover the two navies that start large and have to be spent rather than grown.

Sources

• "The Only HoI4 Navy Guide You'll Ever Need" — VijoPlays, YouTube, 3 August 2026. Published under the title "The Ultimate HoI4 Navy Guide | 2026".
• Ship loadouts are given slot-by-slot in a Google Doc linked from the video description rather than read out on camera. The designs above are the shape of each ship; pull exact module tiers from the doc or from your own tech level.
• Detail is transcribed from the video's auto-generated captions, so some proper nouns may be slightly misspelled — the method is right even where the spelling is not.
• The "from the comments" box collects points raised by viewers foxdavion6865, kleinerprinz99, montymechanizedmarines, apoivre, robertalaverdov8147, elbast0 and WalrusJones185 that are not in the video itself.
• Sections 10 to 15 are game mechanics rather than video content: screening and carrier screening ratios, torpedo penetration, group targeting, piercing, sortie efficiency, submarine reveal rules, mission supremacy shares, the doctrine tracks and the London Naval Treaty caps are taken from the Hearts of Iron IV wiki, read on 22 August 2026.

Heavily patch-dependent by the author's own admission — the framing of the whole video is that the meta destroyer will be nerfed. Carrier overstacking removal, naval bombers no longer targeting the largest ship, and buggy carrier stances are all called out as current-patch behaviour.