diff --git a/.changeset/small-owls-remain.md b/.changeset/small-owls-remain.md
new file mode 100644
index 0000000000..a63ff64935
--- /dev/null
+++ b/.changeset/small-owls-remain.md
@@ -0,0 +1,5 @@
+---
+'svelte': patch
+---
+
+chore: align warning and error objects, add frame property
diff --git a/packages/svelte/scripts/process-messages/templates/compile-errors.js b/packages/svelte/scripts/process-messages/templates/compile-errors.js
index e129eef9f6..349e0b38ef 100644
--- a/packages/svelte/scripts/process-messages/templates/compile-errors.js
+++ b/packages/svelte/scripts/process-messages/templates/compile-errors.js
@@ -1,54 +1,17 @@
-/** @import { Location } from 'locate-character' */
-import * as state from './state.js';
+import { CompileDiagnostic } from './utils/compile_diagnostic.js';
 
 /** @typedef {{ start?: number, end?: number }} NodeLike */
 
-export class InternalCompileError extends Error {
+export class InternalCompileError extends CompileDiagnostic {
 	name = 'CompileError';
 
-	filename = state.filename;
-
-	/** @type {[number, number] | undefined} */
-	position = undefined;
-
-	/** @type {Location | undefined} */
-	start = undefined;
-
-	/** @type {Location | undefined} */
-	end = undefined;
-
 	/**
-	 *
 	 * @param {string} code
 	 * @param {string} message
 	 * @param {[number, number] | undefined} position
 	 */
 	constructor(code, message, position) {
-		super(message);
-
-		this.code = code;
-		this.position = position;
-
-		if (position) {
-			this.start = state.locator(position[0]);
-			this.end = state.locator(position[1]);
-		}
-	}
-
-	toString() {
-		let out = `${this.name}: ${this.message}`;
-
-		out += `\n(${this.code})`;
-
-		if (this.filename) {
-			out += `\n${this.filename}`;
-
-			if (this.start) {
-				out += `${this.start.line}:${this.start.column}`;
-			}
-		}
-
-		return out;
+		super(code, message, position);
 	}
 }
 
@@ -65,7 +28,7 @@ function e(node, code, message) {
 	throw new InternalCompileError(
 		code,
 		message,
-		start !== undefined && end !== undefined ? [start, end] : undefined
+		start !== undefined ? [start, end ?? start] : undefined
 	);
 }
 
diff --git a/packages/svelte/scripts/process-messages/templates/compile-warnings.js b/packages/svelte/scripts/process-messages/templates/compile-warnings.js
index d6a0cd6a0b..c8bd7993c0 100644
--- a/packages/svelte/scripts/process-messages/templates/compile-warnings.js
+++ b/packages/svelte/scripts/process-messages/templates/compile-warnings.js
@@ -1,7 +1,21 @@
-import { filename, locator, warnings, ignore_stack, ignore_map } from './state.js';
+import { warnings, ignore_stack, ignore_map } from './state.js';
+import { CompileDiagnostic } from './utils/compile_diagnostic.js';
 
 /** @typedef {{ start?: number, end?: number }} NodeLike */
 
+export class InternalCompileWarning extends CompileDiagnostic {
+	name = 'CompileWarning';
+
+	/**
+	 * @param {string} code
+	 * @param {string} message
+	 * @param {[number, number] | undefined} position
+	 */
+	constructor(code, message, position) {
+		super(code, message, position);
+	}
+}
+
 /**
  * @param {null | NodeLike} node
  * @param {string} code
@@ -14,13 +28,13 @@ function w(node, code, message) {
 	}
 	if (stack && stack.at(-1)?.has(code)) return;
 
-	warnings.push({
-		code,
-		message,
-		filename,
-		start: node?.start !== undefined ? locator(node.start) : undefined,
-		end: node?.end !== undefined ? locator(node.end) : undefined
-	});
+	warnings.push(
+		new InternalCompileWarning(
+			code,
+			message,
+			node && node.start !== undefined ? [node.start, node.end ?? node.start] : undefined
+		)
+	);
 }
 
 export const codes = CODES;
diff --git a/packages/svelte/src/compiler/errors.js b/packages/svelte/src/compiler/errors.js
index c26586fb1c..7e0b5dd995 100644
--- a/packages/svelte/src/compiler/errors.js
+++ b/packages/svelte/src/compiler/errors.js
@@ -1,50 +1,18 @@
 /* This file is generated by scripts/process-messages/index.js. Do not edit! */
 
-/** @import { Location } from 'locate-character' */
-import * as state from './state.js';
+import { CompileDiagnostic } from './utils/compile_diagnostic.js';
 
 /** @typedef {{ start?: number, end?: number }} NodeLike */
-export class InternalCompileError extends Error {
+export class InternalCompileError extends CompileDiagnostic {
 	name = 'CompileError';
-	filename = state.filename;
-	/** @type {[number, number] | undefined} */
-	position = undefined;
-	/** @type {Location | undefined} */
-	start = undefined;
-	/** @type {Location | undefined} */
-	end = undefined;
 
 	/**
-	 *
 	 * @param {string} code
 	 * @param {string} message
 	 * @param {[number, number] | undefined} position
 	 */
 	constructor(code, message, position) {
-		super(message);
-		this.code = code;
-		this.position = position;
-
-		if (position) {
-			this.start = state.locator(position[0]);
-			this.end = state.locator(position[1]);
-		}
-	}
-
-	toString() {
-		let out = `${this.name}: ${this.message}`;
-
-		out += `\n(${this.code})`;
-
-		if (this.filename) {
-			out += `\n${this.filename}`;
-
-			if (this.start) {
-				out += `${this.start.line}:${this.start.column}`;
-			}
-		}
-
-		return out;
+		super(code, message, position);
 	}
 }
 
@@ -58,7 +26,7 @@ function e(node, code, message) {
 	const start = typeof node === 'number' ? node : node?.start;
 	const end = typeof node === 'number' ? node : node?.end;
 
-	throw new InternalCompileError(code, message, start !== undefined && end !== undefined ? [start, end] : undefined);
+	throw new InternalCompileError(code, message, start !== undefined ? [start, end ?? start] : undefined);
 }
 
 /**
diff --git a/packages/svelte/src/compiler/state.js b/packages/svelte/src/compiler/state.js
index 1e094d95fd..64b9fe591c 100644
--- a/packages/svelte/src/compiler/state.js
+++ b/packages/svelte/src/compiler/state.js
@@ -14,6 +14,12 @@ export let warnings = [];
  */
 export let filename;
 
+/**
+ * The original source code
+ * @type {string}
+ */
+export let source;
+
 export let locator = getLocator('', { offsetLine: 1 });
 
 /**
@@ -43,10 +49,11 @@ export function pop_ignore() {
 }
 
 /**
- * @param {string} source
+ * @param {string} _source
  * @param {{ filename?: string, rootDir?: string }} options
  */
-export function reset(source, options) {
+export function reset(_source, options) {
+	source = _source;
 	const root_dir = options.rootDir?.replace(/\\/g, '/');
 	filename = options.filename?.replace(/\\/g, '/');
 
diff --git a/packages/svelte/src/compiler/types/index.d.ts b/packages/svelte/src/compiler/types/index.d.ts
index 129b5da175..9574491756 100644
--- a/packages/svelte/src/compiler/types/index.d.ts
+++ b/packages/svelte/src/compiler/types/index.d.ts
@@ -6,13 +6,12 @@ import type {
 	Identifier,
 	ImportDeclaration
 } from 'estree';
-import type { Location } from 'locate-character';
 import type { SourceMap } from 'magic-string';
 import type { Context } from 'zimmerframe';
 import type { Scope } from '../phases/scope.js';
 import type { Css } from './css.js';
 import type { EachBlock, Namespace, SvelteNode, SvelteOptions } from './template.js';
-import type { InternalCompileError } from '../errors.js';
+import type { ICompileDiagnostic } from '../utils/compile_diagnostic.js';
 
 /** The return value of `compile` from `svelte/compiler` */
 export interface CompileResult {
@@ -51,16 +50,9 @@ export interface CompileResult {
 	ast: any;
 }
 
-export interface Warning {
-	start?: Location;
-	end?: Location;
-	// TODO there was pos: number in Svelte 4 - do we want to add it back?
-	code: string;
-	message: string;
-	filename?: string;
-}
+export interface Warning extends ICompileDiagnostic {}
 
-export interface CompileError extends InternalCompileError {}
+export interface CompileError extends ICompileDiagnostic {}
 
 export type CssHashGetter = (args: {
 	name: string;
diff --git a/packages/svelte/src/compiler/utils/compile_diagnostic.js b/packages/svelte/src/compiler/utils/compile_diagnostic.js
new file mode 100644
index 0000000000..fa36416a06
--- /dev/null
+++ b/packages/svelte/src/compiler/utils/compile_diagnostic.js
@@ -0,0 +1,105 @@
+/** @import { Location } from 'locate-character' */
+import * as state from '../state.js';
+
+const regex_tabs = /^\t+/;
+
+/**
+ * @param {string} str
+ */
+function tabs_to_spaces(str) {
+	return str.replace(regex_tabs, (match) => match.split('\t').join('  '));
+}
+
+/**
+ * @param {string} source
+ * @param {number} line
+ * @param {number} column
+ */
+function get_code_frame(source, line, column) {
+	const lines = source.split('\n');
+	const frame_start = Math.max(0, line - 2);
+	const frame_end = Math.min(line + 3, lines.length);
+	const digits = String(frame_end + 1).length;
+	return lines
+		.slice(frame_start, frame_end)
+		.map((str, i) => {
+			const is_error_line = frame_start + i === line;
+			const line_num = String(i + frame_start + 1).padStart(digits, ' ');
+			if (is_error_line) {
+				const indicator =
+					' '.repeat(digits + 2 + tabs_to_spaces(str.slice(0, column)).length) + '^';
+				return `${line_num}: ${tabs_to_spaces(str)}\n${indicator}`;
+			}
+			return `${line_num}: ${tabs_to_spaces(str)}`;
+		})
+		.join('\n');
+}
+
+/**
+ * @typedef {{
+ * 	code: string;
+ * 	message: string;
+ * 	filename?: string;
+ * 	start?: Location;
+ * 	end?: Location;
+ * 	position?: [number, number];
+ * 	frame?: string;
+ * }} ICompileDiagnostic */
+
+/** @implements {ICompileDiagnostic} */
+export class CompileDiagnostic extends Error {
+	name = 'CompileDiagnostic';
+
+	/**
+	 * @param {string} code
+	 * @param {string} message
+	 * @param {[number, number] | undefined} position
+	 */
+	constructor(code, message, position) {
+		super(message);
+		this.code = code;
+
+		if (state.filename) {
+			this.filename = state.filename;
+		}
+
+		if (position) {
+			this.position = position;
+			this.start = state.locator(position[0]);
+			this.end = state.locator(position[1]);
+			if (this.start && this.end) {
+				this.frame = get_code_frame(state.source, this.start.line - 1, this.end.column);
+			}
+		}
+	}
+
+	toString() {
+		let out = `${this.code}: ${this.message}`;
+
+		if (this.filename) {
+			out += `\n${this.filename}`;
+
+			if (this.start) {
+				out += `:${this.start.line}:${this.start.column}`;
+			}
+		}
+
+		if (this.frame) {
+			out += `\n${this.frame}`;
+		}
+
+		return out;
+	}
+
+	toJSON() {
+		return {
+			code: this.code,
+			message: this.message,
+			filename: this.filename,
+			start: this.start,
+			end: this.end,
+			position: this.position,
+			frame: this.frame
+		};
+	}
+}
diff --git a/packages/svelte/src/compiler/warnings.js b/packages/svelte/src/compiler/warnings.js
index 7f40eec02b..2518c6c38a 100644
--- a/packages/svelte/src/compiler/warnings.js
+++ b/packages/svelte/src/compiler/warnings.js
@@ -1,14 +1,22 @@
 /* This file is generated by scripts/process-messages/index.js. Do not edit! */
 
-import {
-	filename,
-	locator,
-	warnings,
-	ignore_stack,
-	ignore_map
-} from './state.js';
+import { warnings, ignore_stack, ignore_map } from './state.js';
+import { CompileDiagnostic } from './utils/compile_diagnostic.js';
 
 /** @typedef {{ start?: number, end?: number }} NodeLike */
+export class InternalCompileWarning extends CompileDiagnostic {
+	name = 'CompileWarning';
+
+	/**
+	 * @param {string} code
+	 * @param {string} message
+	 * @param {[number, number] | undefined} position
+	 */
+	constructor(code, message, position) {
+		super(code, message, position);
+	}
+}
+
 /**
  * @param {null | NodeLike} node
  * @param {string} code
@@ -22,14 +30,7 @@ function w(node, code, message) {
 	}
 
 	if (stack && stack.at(-1)?.has(code)) return;
-
-	warnings.push({
-		code,
-		message,
-		filename,
-		start: node?.start !== undefined ? locator(node.start) : undefined,
-		end: node?.end !== undefined ? locator(node.end) : undefined
-	});
+	warnings.push(new InternalCompileWarning(code, message, node && node.start !== undefined ? [node.start, node.end ?? node.start] : undefined));
 }
 
 export const codes = [
diff --git a/packages/svelte/tests/css/test.ts b/packages/svelte/tests/css/test.ts
index d17f7e9c6b..b4b25fc479 100644
--- a/packages/svelte/tests/css/test.ts
+++ b/packages/svelte/tests/css/test.ts
@@ -10,6 +10,8 @@ import type { CompileOptions, Warning } from '#compiler';
 
 function normalize_warning(warning: Warning) {
 	delete warning.filename;
+	delete warning.position;
+	delete warning.frame;
 	return warning;
 }
 
diff --git a/packages/svelte/types/index.d.ts b/packages/svelte/types/index.d.ts
index 305e1240db..775fd7394b 100644
--- a/packages/svelte/types/index.d.ts
+++ b/packages/svelte/types/index.d.ts
@@ -562,9 +562,9 @@ declare module 'svelte/animate' {
 
 declare module 'svelte/compiler' {
 	import type { AssignmentExpression, ClassDeclaration, Expression, FunctionDeclaration, Identifier, ImportDeclaration, ArrayExpression, MemberExpression, ObjectExpression, Pattern, ArrowFunctionExpression, VariableDeclaration, VariableDeclarator, FunctionExpression, Node, Program, ChainExpression, SimpleCallExpression } from 'estree';
-	import type { Location } from 'locate-character';
 	import type { SourceMap } from 'magic-string';
 	import type { Context } from 'zimmerframe';
+	import type { Location } from 'locate-character';
 	/**
 	 * `compile` converts your `.svelte` source code into a JavaScript module that exports a component
 	 *
@@ -714,16 +714,9 @@ declare module 'svelte/compiler' {
 		ast: any;
 	}
 
-	export interface Warning {
-		start?: Location;
-		end?: Location;
-		// TODO there was pos: number in Svelte 4 - do we want to add it back?
-		code: string;
-		message: string;
-		filename?: string;
-	}
+	export interface Warning extends ICompileDiagnostic {}
 
-	export interface CompileError extends InternalCompileError {}
+	export interface CompileError extends ICompileDiagnostic {}
 
 	type CssHashGetter = (args: {
 		name: string;
@@ -1882,18 +1875,15 @@ declare module 'svelte/compiler' {
 		content: Program;
 		attributes: Attribute[];
 	}
-	class InternalCompileError extends Error {
-		
-		constructor(code: string, message: string, position: [number, number] | undefined);
-		filename: string | undefined;
-		
-		position: [number, number] | undefined;
-		
-		start: Location | undefined;
-		
-		end: Location | undefined;
+	type ICompileDiagnostic = {
 		code: string;
-	}
+		message: string;
+		filename?: string;
+		start?: Location;
+		end?: Location;
+		position?: [number, number];
+		frame?: string;
+	};
 
 	export {};
 }
@@ -2539,14 +2529,7 @@ declare module 'svelte/types/compiler/interfaces' {
 	export type CompileOptions = CompileOptions_1;
 	/** @deprecated import this from 'svelte' instead */
 	export type Warning = Warning_1;
-	interface Warning_1 {
-		start?: Location;
-		end?: Location;
-		// TODO there was pos: number in Svelte 4 - do we want to add it back?
-		code: string;
-		message: string;
-		filename?: string;
-	}
+	interface Warning_1 extends ICompileDiagnostic {}
 
 	type CssHashGetter = (args: {
 		name: string;
@@ -2709,6 +2692,15 @@ declare module 'svelte/types/compiler/interfaces' {
 	 *               (also see https://github.com/sveltejs/svelte/pull/5652)
 	 */
 	type Namespace = 'html' | 'svg' | 'mathml' | 'foreign';
+	type ICompileDiagnostic = {
+		code: string;
+		message: string;
+		filename?: string;
+		start?: Location;
+		end?: Location;
+		position?: [number, number];
+		frame?: string;
+	};
 
 	export {};
 }declare module '*.svelte' {