diff --git a/server/src/lib/score-import/import-types/common/api-cg/popn/converter.test.ts b/server/src/lib/score-import/import-types/common/api-cg/popn/converter.test.ts
new file mode 100644
index 000000000..74a5b5529
--- /dev/null
+++ b/server/src/lib/score-import/import-types/common/api-cg/popn/converter.test.ts
@@ -0,0 +1,122 @@
+import { ConverterAPICGPopn } from "./converter";
+import CreateLogCtx from "lib/logger/logger";
+import t from "tap";
+import { dmf } from "test-utils/misc";
+import type { CGContext, CGPopnScore } from "../types";
+import type { DryScore } from "lib/score-import/framework/common/types";
+
+const logger = CreateLogCtx(__filename);
+
+function mkInput(modifant: Partial<CGPopnScore> = {}) {
+	const validInput: CGPopnScore = {
+		internalId: 0, // this is "i really wanna hurt you"
+		difficulty: 0,
+		coolCount: 100,
+		badCount: 50,
+		greatCount: 15,
+		goodCount: 25,
+		clearFlag: 5, // clear,
+		dateTime: "2019-06-06 08:14:22",
+		score: 87_000,
+		version: 25,
+	};
+
+	return dmf(validInput, modifant);
+}
+
+// we use any here because it's not easy to allow deep partials
+function mkOutput(modifant: any = {}): DryScore<"popn:9B"> {
+	const validOutput: DryScore<"popn:9B"> = {
+		comment: null,
+		game: "popn",
+		importType: "api/cg-dev-popn",
+		timeAchieved: 1559805262000,
+		service: "dev",
+		scoreData: {
+			grade: "A",
+			percent: 87,
+			score: 87000,
+			lamp: "CLEAR",
+			judgements: {
+				cool: 100,
+				great: 15,
+				good: 25,
+				bad: 50,
+			},
+			hitMeta: {
+				specificClearType: "clearCircle",
+			},
+		},
+		scoreMeta: {},
+	};
+
+	return dmf(validOutput, modifant);
+}
+
+t.test("#ConverterAPICGPopn", (t) => {
+	const context: CGContext = {
+		service: "dev",
+		userID: 1,
+	};
+
+	const convert = (modifant: Partial<CGPopnScore> = {}) =>
+		ConverterAPICGPopn(mkInput(modifant), context, "api/cg-dev-popn", logger);
+
+	t.test("Valid Input", async (t) => {
+		const res = await convert();
+
+		t.hasStrict(res, {
+			song: {
+				id: 1,
+			},
+			chart: {
+				difficulty: "Easy",
+				data: {
+					inGameID: 0,
+				},
+			},
+			dryScore: mkOutput(),
+		});
+
+		t.end();
+	});
+
+	t.test("Should cap fails at A grade", async (t) => {
+		const res = await convert({
+			clearFlag: 1,
+			score: 98_000,
+		});
+
+		t.hasStrict(res, {
+			dryScore: mkOutput({
+				scoreData: {
+					lamp: "FAILED",
+					grade: "A",
+					score: 98_000,
+					percent: 98,
+					hitMeta: {
+						specificClearType: "failedCircle",
+					},
+				},
+			}),
+		});
+
+		const res2 = await convert({
+			score: 98_000,
+		});
+
+		t.hasStrict(res2, {
+			dryScore: mkOutput({
+				scoreData: {
+					grade: "S",
+					score: 98_000,
+					percent: 98,
+				},
+			}),
+		});
+
+		t.end();
+	});
+
+	t.end();
+});
diff --git a/server/src/test-utils/mock-db/charts-popn.json b/server/src/test-utils/mock-db/charts-popn.json
index 30b8d3307..6e0f33b5c 100644
--- a/server/src/test-utils/mock-db/charts-popn.json
+++ b/server/src/test-utils/mock-db/charts-popn.json
@@ -9,7 +9,8 @@
 		"rgcID": null,
 		"isPrimary": true,
 		"data": {
-			"hashSHA256": "2c26d666fa7c907e85115dbb279c267c14a263d47b2d46a93f99eae49d779119"
+			"hashSHA256": "2c26d666fa7c907e85115dbb279c267c14a263d47b2d46a93f99eae49d779119",
+			"inGameID": 0
 		},
 		"tierlistInfo": {},
 		"versions": [