diff --git a/app/Models/ExchangeRate.php b/app/Models/ExchangeRate.php
index 495a390e..970a7a49 100644
--- a/app/Models/ExchangeRate.php
+++ b/app/Models/ExchangeRate.php
@@ -2,11 +2,14 @@
 
 namespace App\Models;
 
+use Carbon\Carbon;
 use Database\Factories\ExchangeRateFactory;
 use Illuminate\Database\Eloquent\Factories\HasFactory;
 use Illuminate\Database\Eloquent\Model;
 
 /**
+ * @property string $base_currency
+ * @property Carbon $date
  * @property array<string, float> $rates
  */
 class ExchangeRate extends Model
diff --git a/app/Services/AccountMetricsService.php b/app/Services/AccountMetricsService.php
index 0f98f1c4..588e0fc7 100644
--- a/app/Services/AccountMetricsService.php
+++ b/app/Services/AccountMetricsService.php
@@ -27,6 +27,7 @@ class AccountMetricsService
 
         $accountIds = $accounts->pluck('id');
         $lookup = BalanceLookup::forAccounts($accountIds, $rangeStart, $now->copy());
+        $this->preloadExchangeRates($userCurrency, $accounts, $this->monthlyEndDateStrings($rangeStart, $now));
 
         $metrics = [];
 
@@ -90,6 +91,7 @@ class AccountMetricsService
 
         $lookupEnd = Carbon::now()->gt($end) ? Carbon::now() : $end->copy();
         $lookup = BalanceLookup::forAccounts($accountIds, $start->copy()->startOfMonth(), $lookupEnd);
+        $this->preloadExchangeRates($userCurrency, $accounts, $this->monthlyEndDateStrings($start, $end));
 
         $points = [];
         $current = $start->copy()->startOfMonth();
@@ -173,6 +175,7 @@ class AccountMetricsService
     {
         $accountIds = $accounts->pluck('id');
         $lookup = BalanceLookup::forAccounts($accountIds, $start, $end);
+        $this->preloadExchangeRates($userCurrency, $accounts, $this->dailyDateStrings($start, $end));
 
         $points = [];
         $current = $start->copy();
@@ -240,6 +243,56 @@ class AccountMetricsService
         return $this->exchangeRateService->convert($sourceCurrency, $targetCurrency, $balance, $date);
     }
 
+    /**
+     * @param  Collection<int, Account>  $accounts
+     * @param  list<string>  $dates
+     */
+    private function preloadExchangeRates(string $userCurrency, Collection $accounts, array $dates): void
+    {
+        $hasForeignCurrencyAccount = $accounts->contains(
+            fn (Account $account): bool => strcasecmp($account->currency_code, $userCurrency) !== 0,
+        );
+
+        if (! $hasForeignCurrencyAccount) {
+            return;
+        }
+
+        $this->exchangeRateService->preloadRates($userCurrency, $dates);
+    }
+
+    /**
+     * @return list<string>
+     */
+    private function monthlyEndDateStrings(Carbon $start, Carbon $end): array
+    {
+        $dates = [];
+        $current = $start->copy()->startOfMonth();
+        $endMonth = $end->copy()->startOfMonth();
+
+        while ($current->lte($endMonth)) {
+            $dates[] = $current->copy()->endOfMonth()->toDateString();
+            $current->addMonth();
+        }
+
+        return $dates;
+    }
+
+    /**
+     * @return list<string>
+     */
+    private function dailyDateStrings(Carbon $start, Carbon $end): array
+    {
+        $dates = [];
+        $current = $start->copy();
+
+        while ($current->lte($end)) {
+            $dates[] = $current->toDateString();
+            $current->addDay();
+        }
+
+        return $dates;
+    }
+
     /**
      * Format a month label: "M" for current year, "M 'y" for previous years.
      */
diff --git a/app/Services/ExchangeRateService.php b/app/Services/ExchangeRateService.php
index 4dc5f74a..7c3b4d3c 100644
--- a/app/Services/ExchangeRateService.php
+++ b/app/Services/ExchangeRateService.php
@@ -8,6 +8,12 @@ use Illuminate\Support\Facades\Log;
 
 class ExchangeRateService
 {
+    /** @var array<string, array<string, float>> */
+    private array $ratesCache = [];
+
+    /** @var array<string, true> */
+    private array $databaseMissCache = [];
+
     public function __construct(private CurrencyConversionService $currencyApi) {}
 
     /**
@@ -25,7 +31,7 @@ class ExchangeRateService
         $source = strtolower($source);
         $target = strtolower($target);
 
-        if ($source === $target) {
+        if ($source === $target || $amountInCents === 0) {
             return $amountInCents;
         }
 
@@ -55,20 +61,22 @@ class ExchangeRateService
     public function getRates(string $baseCurrency, string $date): array
     {
         $baseCurrency = strtolower($baseCurrency);
+        $date = $this->normalizeDate($date);
+        $cacheKey = $this->cacheKey($baseCurrency, $date);
 
-        // Cap future dates to today — the API only has rates up to the current date.
-        $today = Carbon::today()->toDateString();
-        if ($date > $today) {
-            $date = $today;
+        if (array_key_exists($cacheKey, $this->ratesCache)) {
+            return $this->ratesCache[$cacheKey];
         }
 
-        $cached = ExchangeRate::query()
-            ->where('base_currency', $baseCurrency)
-            ->where('date', $date)
-            ->first();
+        if (! isset($this->databaseMissCache[$cacheKey])) {
+            $cached = ExchangeRate::query()
+                ->where('base_currency', $baseCurrency)
+                ->where('date', $date)
+                ->first();
 
-        if ($cached) {
-            return $cached->rates;
+            if ($cached) {
+                return $this->ratesCache[$cacheKey] = $cached->rates;
+            }
         }
 
         $rates = $this->currencyApi->getRatesForCurrency($baseCurrency, $date);
@@ -81,6 +89,52 @@ class ExchangeRateService
             ]);
         }
 
-        return $rates;
+        return $this->ratesCache[$cacheKey] = $rates;
+    }
+
+    /**
+     * Preload cached exchange rates for many dates in one query.
+     *
+     * @param  iterable<int, string>  $dates
+     */
+    public function preloadRates(string $baseCurrency, iterable $dates): void
+    {
+        $baseCurrency = strtolower($baseCurrency);
+        $dates = collect($dates)
+            ->map(fn (string $date): string => $this->normalizeDate($date))
+            ->unique()
+            ->reject(fn (string $date): bool => array_key_exists($this->cacheKey($baseCurrency, $date), $this->ratesCache))
+            ->values();
+
+        if ($dates->isEmpty()) {
+            return;
+        }
+
+        ExchangeRate::query()
+            ->where('base_currency', $baseCurrency)
+            ->whereIn('date', $dates->all())
+            ->get(['base_currency', 'date', 'rates'])
+            ->each(function (ExchangeRate $exchangeRate): void {
+                $date = $exchangeRate->date->toDateString();
+                $this->ratesCache[$this->cacheKey($exchangeRate->base_currency, $date)] = $exchangeRate->rates;
+            });
+
+        $dates
+            ->reject(fn (string $date): bool => array_key_exists($this->cacheKey($baseCurrency, $date), $this->ratesCache))
+            ->each(function (string $date) use ($baseCurrency): void {
+                $this->databaseMissCache[$this->cacheKey($baseCurrency, $date)] = true;
+            });
+    }
+
+    private function normalizeDate(string $date): string
+    {
+        $today = Carbon::today()->toDateString();
+
+        return $date > $today ? $today : $date;
+    }
+
+    private function cacheKey(string $baseCurrency, string $date): string
+    {
+        return strtolower($baseCurrency).'|'.$date;
     }
 }
diff --git a/tests/Feature/DashboardAnalyticsTest.php b/tests/Feature/DashboardAnalyticsTest.php
index 4b84c93d..823d0cf7 100644
--- a/tests/Feature/DashboardAnalyticsTest.php
+++ b/tests/Feature/DashboardAnalyticsTest.php
@@ -10,6 +10,7 @@ use App\Models\LoanDetail;
 use App\Models\RealEstateDetail;
 use App\Models\Transaction;
 use App\Models\User;
+use Illuminate\Support\Facades\DB;
 use Illuminate\Support\Facades\Http;
 
 beforeEach(function () {
@@ -364,6 +365,54 @@ test('net worth evolution converts foreign currency accounts using cached exchan
     Http::assertNothingSent();
 });
 
+test('net worth evolution preloads exchange rates for the requested date range', function () {
+    $eurAccount = Account::factory()->create([
+        'user_id' => $this->user->id,
+        'type' => AccountType::Savings,
+        'currency_code' => 'EUR',
+    ]);
+
+    $end = now()->subMonthNoOverflow()->endOfMonth();
+    $start = $end->copy()->subMonthsNoOverflow(11)->startOfMonth();
+    $current = $start->copy();
+
+    while ($current->lte($end)) {
+        $date = $current->copy()->endOfMonth();
+
+        AccountBalance::factory()->create([
+            'account_id' => $eurAccount->id,
+            'balance_date' => $date,
+            'balance' => 100000,
+        ]);
+
+        ExchangeRate::factory()->create([
+            'base_currency' => 'usd',
+            'date' => $date->toDateString(),
+            'rates' => ['eur' => 0.90],
+        ]);
+
+        $current->addMonth();
+    }
+
+    $exchangeRateSelects = [];
+    DB::listen(function ($query) use (&$exchangeRateSelects): void {
+        if (str_starts_with(strtolower($query->sql), 'select') && str_contains($query->sql, 'exchange_rates')) {
+            $exchangeRateSelects[] = $query->sql;
+        }
+    });
+
+    $response = $this->getJson('/api/dashboard/net-worth-evolution?'.http_build_query([
+        'from' => $start->toDateString(),
+        'to' => $end->toDateString(),
+    ]));
+
+    $response->assertOk();
+
+    expect($response->json('data'))->toHaveCount(12);
+    expect($exchangeRateSelects)->toHaveCount(1);
+    Http::assertNothingSent();
+});
+
 test('net worth evolution uses last balance of each month per account', function () {
     $account = Account::factory()->create([
         'user_id' => $this->user->id,
diff --git a/tests/Feature/ExchangeRateServiceTest.php b/tests/Feature/ExchangeRateServiceTest.php
index 514fe561..3c418aaf 100644
--- a/tests/Feature/ExchangeRateServiceTest.php
+++ b/tests/Feature/ExchangeRateServiceTest.php
@@ -2,6 +2,7 @@
 
 use App\Models\ExchangeRate;
 use App\Services\ExchangeRateService;
+use Illuminate\Support\Facades\DB;
 use Illuminate\Support\Facades\Http;
 
 test('convert returns same amount when source equals target', function () {
@@ -86,6 +87,60 @@ test('convert uses database cache on second call for same currency and date', fu
     Http::assertSentCount(1);
 });
 
+test('convert memoizes exchange rates during service lifetime', function () {
+    Http::fake();
+
+    ExchangeRate::factory()->create([
+        'base_currency' => 'usd',
+        'date' => '2026-01-15',
+        'rates' => [
+            'eur' => 0.85,
+            'gbp' => 0.72,
+        ],
+    ]);
+
+    $exchangeRateSelects = [];
+    DB::listen(function ($query) use (&$exchangeRateSelects): void {
+        if (str_starts_with(strtolower($query->sql), 'select') && str_contains($query->sql, 'exchange_rates')) {
+            $exchangeRateSelects[] = $query->sql;
+        }
+    });
+
+    $service = app(ExchangeRateService::class);
+    $service->convert('EUR', 'USD', 100000, '2026-01-15');
+    $service->convert('GBP', 'USD', 200000, '2026-01-15');
+    $service->getRates('USD', '2026-01-15');
+
+    expect($exchangeRateSelects)->toHaveCount(1);
+    Http::assertNothingSent();
+});
+
+test('preloaded missing rates do not trigger per-date database lookups', function () {
+    Http::fake([
+        'cdn.jsdelivr.net/*currencies/usd*' => Http::response([
+            'usd' => [
+                'eur' => 0.90,
+                'gbp' => 0.75,
+            ],
+        ]),
+    ]);
+
+    $exchangeRateSelects = [];
+    DB::listen(function ($query) use (&$exchangeRateSelects): void {
+        if (str_starts_with(strtolower($query->sql), 'select') && str_contains($query->sql, 'exchange_rates')) {
+            $exchangeRateSelects[] = $query->sql;
+        }
+    });
+
+    $service = app(ExchangeRateService::class);
+    $service->preloadRates('USD', ['2026-02-10', '2026-02-11']);
+    $service->convert('EUR', 'USD', 100000, '2026-02-10');
+    $service->convert('GBP', 'USD', 200000, '2026-02-11');
+
+    expect($exchangeRateSelects)->toHaveCount(1);
+    Http::assertSentCount(2);
+});
+
 test('convert returns unconverted amount when rate is missing', function () {
     ExchangeRate::factory()->create([
         'base_currency' => 'usd',