International US-QWERTY layout with AltGr dead keys via AutoHotkey script (Windows).
In UltimateKEYS, all keys remain exactly organized as US-QWERTY. Except, when AltGr or AltGr+Shift is pressed in combination with another key, other diacritics and symbols are accessible and some keys become dead keys.
In that way, it is - somehow - similar to the layout "United States-International" (on Windows), although this project moves all dead key combinations to the modifiers AltGr and AltGr+Shift. That way, this project solves the most typical caveats, among which the quotes (' and ") can be used as usual (without pressing the spacebar afterwards), while the acute accent (´) and diaeresis (¨) are found under Alt and Alt+Shift respectively. This project has borrowed several aspects from the EurKEY Keyboard Layout.

a -> à a with grave A -> À A with grave e -> è e with grave E -> È E with grave i -> ì i with grave I -> Ì I with grave n -> ǹ n with grave N -> Ǹ N with grave o -> ò o with grave O -> Ò O with grave u -> ù u with grave U -> Ù U with grave w -> ẁ w with grave W -> Ẁ W with grave y -> ỳ y with grave Y -> Ỳ Y with grave (space) -> ` grave accent

a -> ã a with tilde A -> Ã A with tilde e -> ẽ e with tilde E -> Ẽ E with tilde i -> ĩ i with tilde I -> Ĩ I with tilde n -> ñ n with tilde N -> Ñ N with tilde o -> õ o with tilde O -> Õ O with tilde u -> ũ u with tilde U -> Ũ U with tilde v -> ṽ v with tilde V -> Ṽ V with tilde y -> ỹ y with tilde Y -> Ỹ Y with tilde (space) -> ~ tilde

a -> â a with circumflex A -> Â A with circumflex c -> ĉ c with circumflex C -> Ĉ C with circumflex e -> ê e with circumflex E -> Ê E with circumflex g -> ĝ g with circumflex G -> Ĝ G with circumflex h -> ĥ h with circumflex H -> Ĥ H with circumflex i -> î i with circumflex I -> Î I with circumflex j -> ĵ j with circumflex J -> Ĵ J with circumflex o -> ô o with circumflex O -> Ô O with circumflex s -> ŝ s with circumflex S -> Ŝ S with circumflex u -> û u with circumflex U -> Û U with circumflex w -> ŵ w with circumflex W -> Ŵ W with circumflex y -> ŷ y with circumflex Y -> Ŷ Y with circumflex z -> ẑ z with circumflex Z -> Ẑ Z with circumflex (space) -> ^ circumflex accent

a -> ǎ a with caron A -> Ǎ A with caron c -> č c with caron C -> Č C with caron d -> ď d with caron D -> Ď D with caron e -> ě e with caron E -> Ě E with caron g -> ǧ g with caron G -> Ǧ G with caron h -> ȟ h with caron H -> Ȟ H with caron i -> ǐ i with caron I -> Ǐ I with caron j -> ǰ j with caron k -> ǩ k with caron K -> Ǩ K with caron l -> ľ l with caron L -> Ľ L with caron n -> ň n with caron N -> Ň N with caron o -> ǒ o with caron O -> Ǒ O with caron r -> ř r with caron R -> Ř R with caron s -> š s with caron S -> Š S with caron t -> ť t with caron T -> Ť T with caron u -> ǔ u with caron U -> Ǔ U with caron z -> ž z with caron Z -> Ž Z with caron (space) -> ˇ caron

a -> å a with ring above A -> Å A with ring above ä (AltGr + a) -> ȧ a with dot above Ä (AltGr + A) -> Ȧ a with dot above b -> ḃ b with dot above B -> Ḃ B with dot above c -> ċ c with dot above C -> Ċ C with dot above d -> ḋ d with dot above D -> Ḋ D with dot above e -> ė e with dot above E -> Ė E with dot above f -> ḟ f with dot above F -> Ḟ F with dot above g -> ġ g with dot above G -> Ġ G with dot above h -> ḣ h with dot above H -> Ḣ H with dot above i -> ı dotless i (Turkish, Azerbaijani) I -> İ I with dot above (Turkish, Azerbaijani) m -> ṁ m with dot above M -> Ṁ M with dot above n -> ṅ n with dot above N -> Ṅ N with dot above o -> ȯ o with dot above O -> Ȯ O with dot above p -> ṗ p with dot above P -> Ṗ P with dot above r -> ṙ r with dot above R -> Ṙ R with dot above s -> ṡ s with dot above S -> Ṡ S with dot above t -> ṫ t with dot above T -> Ṫ T with dot above u -> ů u with ring above U -> Ů U with ring above w -> ẘ w with ring above å (AltGr + w) -> ẇ w with dot above Å (AltGr + W) -> Ẇ W with dot above x -> ẋ x with dot above X -> Ẋ X with dot above y -> ẙ y with ring above ÿ (AltGr + y) -> ẏ y with dot above Ÿ (AltGr + Y) -> Ẏ Y with dot above z -> ż z with dot above Z -> Ż Z with dot above (space) -> ˙ dot above

a -> ā a with macron A -> Ā A with macron æ -> ǣ ae with macron Æ -> Ǣ AE with macron b -> ƀ b with stroke B -> Ƀ B with stroke d -> đ d with stroke D -> Đ D with stroke e -> ē e with macron E -> Ē E with macron g -> ḡ g with macron G -> Ḡ G with macron h -> ħ h with stroke H -> Ħ H with stroke i -> ī i with macron I -> Ī I with macron l -> ł l with stroke L -> Ł L with stroke ø (AltGr + l) -> ḻ l with line below Ø (AltGr + L) -> Ḻ L with line below o -> ō o with macron O -> Ō O with macron t -> ŧ t with stroke T -> Ŧ T with stroke u -> ū u with macron U -> Ū U with macron y -> ȳ y with macron Y -> Ȳ Y with macron (space) -> ¯ macron

a -> ą a with ogonek A -> Ą A with ogonek c -> ç c with cedilla C -> Ç C with cedilla d -> ḑ d with cedilla D -> Ḑ D with cedilla e -> ę e with ogonek E -> Ę E with ogonek ë (AltGr + e) -> ȩ e with cedilla Ë (AltGr + E) -> Ȩ E with cedilla g -> ģ g with cedilla G -> Ģ G with cedilla h -> ḩ h with cedilla H -> Ḩ H with cedilla i -> į i with ogonek I -> Į I with ogonek k -> ķ k with cedilla K -> Ķ K with cedilla l -> ļ l with cedilla L -> Ļ L with cedilla n -> ņ n with cedilla N -> Ņ N with cedilla o -> ǫ o with ogonek O -> Ǫ O with ogonek r -> ŗ r with cedilla R -> Ŗ R with cedilla s -> ş s with cedilla S -> Ş S with cedilla t -> ţ t with cedilla T -> Ţ T with cedilla u -> ų u with ogonek U -> Ų U with ogonek . -> ˛ ogonek (space) -> ¸ cedilla

a -> ă a with breve A -> Ă A with breve e -> ĕ e with breve E -> Ĕ E with breve f -> ə small letter schwa (Azerbaijani) F -> Ə capital letter schwa (Azerbaijani) g -> ğ g with breve G -> Ğ G with breve i -> ĭ i with breve I -> Ĭ I with breve j -> ij ligature ij J -> IJ ligature IJ n -> ŋ small letter eng(ma) N -> Ŋ capital letter eng(ma) o -> ŏ o with breve O -> Ŏ O with breve s -> ș s with comma below (Romanian) S -> Ș S with comma below (Romanian) t -> ț t with comma below (Romanian) T -> Ț T with comma below (Romanian) u -> ŭ u with breve U -> Ŭ U with breve (space) -> ˘ breve

a -> á a with acute A -> Á A with acute b -> ɓ b with hook B -> Ɓ B with hook c -> ć c with acute C -> Ć C with acute ç -> ḉ c with cedilla and acute Ç -> Ḉ C with cedilla and acute e -> é e with acute E -> É E with acute i -> í i with acute I -> Í I with acute g -> ǵ g with acute G -> Ǵ G with acute k -> ḱ k with acute K -> Ḱ K with acute l -> ĺ l with acute L -> Ĺ L with acute m -> ḿ m with acute M -> Ḿ M with acute n -> ń n with acute N -> Ń N with acute o -> ó o with acute O -> Ó O with acute ö (AltGr + o) -> ő o with double acute Ö (AltGr + O) -> Ő O with double acute p -> ṕ p with acute P -> Ṕ P with acute r -> ŕ r with acute R -> Ŕ R with acute s -> ś s with acute S -> Ś S with acute u -> ú u with acute U -> Ú U with acute ü (AltGr + u) -> ű u with double acute Ü (AltGr + U) -> Ű U with double acute w -> ẃ w with acute W -> Ẃ W with acute y -> ý y with acute Y -> Ý Y with acute z -> ź z with acute Z -> Ź Z with acute æ -> ǽ ae with acute Æ -> Ǽ AE with acute ø -> ǿ o with stroke and acute Ø -> Ǿ O with stroke and acute (space) -> ´ acute accent

a -> ä a with diaeresis A -> Ä A with diaeresis e -> ë e with diaeresis E -> Ë E with diaeresis h -> ḧ h with diaeresis H -> Ḧ H with diaeresis i -> ï i with diaeresis I -> Ï I with diaeresis o -> ö o with diaeresis O -> Ö O with diaeresis t -> ẗ t with diaeresis u -> ü u with diaeresis U -> Ü U with diaeresis w -> ẅ w with diaeresis W -> Ẅ W with diaeresis x -> ẍ x with diaeresis X -> Ẍ X with diaeresis y -> ÿ y with diaeresis Y -> Ÿ Y with diaeresis (space) -> ¨ diaeresis

a -> α small alpha A -> Α capital alpha b -> β small beta B -> Β capital beta v -> β small beta V -> Β capital beta g -> γ small gamma G -> Γ capital gamma d -> δ small delta D -> Δ capital delta e -> ε small epsilon E -> Ε capital epsilon z -> ζ small zeta Z -> Ζ capital zeta i -> η small eta I -> Η capital eta h -> θ small theta H -> Θ capital theta j -> ι small iota J -> Ι capital iota k -> κ small kappa K -> Κ capital kappa l -> λ small lambda L -> Λ capital lambda m -> μ small mu M -> Μ capital mu n -> ν small nu N -> Ν capital nu x -> ξ small xi X -> Ξ capital xi o -> ο small omikron O -> Ο capital omikron p -> π small pi P -> Π capital pi r -> ρ small rho R -> Ρ capital rho s -> σ small sigma S -> Σ capital sigma ß -> ς small sigma, in word-final position ẞ -> Σ capital sigma t -> τ small tau T -> Τ capital tau y -> υ small upsilon Y -> Υ capital upsilon f -> φ small phi F -> Φ capital phi c -> χ small chi C -> Χ capital chi w -> ψ small psi W -> Ψ capital psi q -> ω small omega Q -> Ω capital omega u -> ω small omega U -> Ω capital omega (space) -> μ small mu

a -> ª feminine ordinal indicator (Spanish, Portuguese, Italian, Galician) A -> ª feminine ordinal indicator (Spanish, Portuguese, Italian, Galician) b -> • bullet B -> ¦ broken bar c -> © copyright sign C -> ¤ currency sign d -> † dagger D -> ‡ double dagger e -> ℮ estimated symbol E -> … ellipsis f -> ♀ Venus symbol (female) F -> ♀ Venus symbol (female) h -> ⁃ hyphen bullet H -> ⁃ hyphen bullet i -> ∞ infinity symbol I -> ∞ infinity symbol l -> ℓ script small l L -> ℓ script small l m -> ♂ Mars symbol (male) M -> ♂ Mars symbol (male) n -> ⁿ superscript n N -> ¬ not sign o -> º masculine ordinal indicator (Spanish, Portuguese, Italian, Galician) O -> º masculine ordinal indicator (Spanish, Portuguese, Italian, Galician) p -> ¶ pilcrow sign P -> ¶ pilcrow sign r -> ® registered sign R -> ® registered sign s -> § section sign S -> § section sign t -> ™ trademark symbol T -> ™ trademark symbol v -> → rightwards arrow V -> ⇒ rightwards double arrow x -> ✗ ballot x X -> ✗ ballot x y -> ✓ check mark Y -> ✓ check mark z -> ← leftwards arrow Z -> ⇐ leftwards double arrow 1 -> ≠ not equal to ! -> ≠ not equal to 2 -> √ square root @ -> √ square root 3 -> ∛ cube root # -> ∛ cube root 4 -> ∜ fourth root $ -> ∜ fourth root 5 -> ‰ per mille sign % -> ‰ per mille sign 6 -> ƒ f with hook ^ -> ƒ f with hook 7 -> № numero sign & -> № numero sign 8 -> · middle dot * -> · middle dot ` -> ≈ almost equal to ~ -> ≈ almost equal to = -> ↔ left right arrow + -> ⇔ left right double arrow , -> ≤ less-than or equal to < -> ≤ less-than or equal to . -> ≥ greater-than or equal to > -> ≥ greater-than or equal to - -> ± plus-minus sign _ -> ± plus-minus sign \ -> ⁞ vertical four dots | -> ⁞ vertical four dots (space) -> ⁿ superscript n