diff --git a/src/app/dashboard/financeiro/financeiro-client.test.tsx b/src/app/dashboard/financeiro/financeiro-client.test.tsx
index edb0d563..3b986b00 100644
--- a/src/app/dashboard/financeiro/financeiro-client.test.tsx
+++ b/src/app/dashboard/financeiro/financeiro-client.test.tsx
@@ -129,13 +129,13 @@ describe('FinanceiroClient', () => {
   it('renders "Inadimplente" badge for each student', () => {
     render(<FinanceiroClient initialInadimplentes={mockInadimplentes} />);
     const badges = screen.getAllByText('Inadimplente');
-    expect(badges.length).toBe(2);
+    expect(badges).toHaveLength(2);
   });
 
   it('renders "Registrar Pagamento" buttons', () => {
     render(<FinanceiroClient initialInadimplentes={mockInadimplentes} />);
     const buttons = screen.getAllByText('Registrar Pagamento');
-    expect(buttons.length).toBe(2);
+    expect(buttons).toHaveLength(2);
   });
 
   it('shows empty state when no inadimplentes', () => {
diff --git a/src/app/dashboard/treinos/__tests__/nan-guards.test.ts b/src/app/dashboard/treinos/__tests__/nan-guards.test.ts
index 63bc8076..a313a3ee 100644
--- a/src/app/dashboard/treinos/__tests__/nan-guards.test.ts
+++ b/src/app/dashboard/treinos/__tests__/nan-guards.test.ts
@@ -25,7 +25,7 @@ describe('NaN guard patterns', () => {
 
   it('empty string becomes undefined with ||, not empty string', () => {
     const empty = '';
-    expect(empty || undefined).toBe(undefined);
+    expect(empty || undefined).toBeUndefined();
     expect(empty ?? undefined).toBe(''); // '' passes through ??
   });
 
diff --git a/src/components/WorkoutSession.test.tsx b/src/components/WorkoutSession.test.tsx
index 868fc5a8..2c20ddf3 100644
--- a/src/components/WorkoutSession.test.tsx
+++ b/src/components/WorkoutSession.test.tsx
@@ -129,8 +129,8 @@ describe('WorkoutSession', () => {
     render(<WorkoutSession treino={mockTreino} onFinish={mockOnFinish} onCancel={mockOnCancel} />);
     const pesoInputs = screen.getAllByPlaceholderText('Peso (kg)');
     const repsInputs = screen.getAllByPlaceholderText('Reps');
-    expect(pesoInputs.length).toBe(3);
-    expect(repsInputs.length).toBe(3);
+    expect(pesoInputs).toHaveLength(3);
+    expect(repsInputs).toHaveLength(3);
   });
 
   it('disables "Anterior" button on first exercise', () => {
diff --git a/src/components/dashboard-nav.test.tsx b/src/components/dashboard-nav.test.tsx
index 7584b20b..b9eac339 100644
--- a/src/components/dashboard-nav.test.tsx
+++ b/src/components/dashboard-nav.test.tsx
@@ -125,7 +125,7 @@ describe('DashboardNav', () => {
     const activeButtons = menuButtons.filter(
       (btn) => btn.getAttribute('data-is-active') === 'true'
     );
-    expect(activeButtons.length).toBe(1);
+    expect(activeButtons).toHaveLength(1);
   });
 
   it('links have correct href attributes', () => {
diff --git a/src/components/dashboard/aluno/card-feedback.test.tsx b/src/components/dashboard/aluno/card-feedback.test.tsx
index a609a1cd..e4af5f0a 100644
--- a/src/components/dashboard/aluno/card-feedback.test.tsx
+++ b/src/components/dashboard/aluno/card-feedback.test.tsx
@@ -34,7 +34,7 @@ describe('CardFeedback', () => {
     render(<CardFeedback feedback={null} isLoading={true} />);
     expect(screen.getByText(/Pulsando Bio-Dados/i)).toBeTruthy();
     const skeletons = screen.getAllByTestId('skeleton');
-    expect(skeletons.length).toBe(3);
+    expect(skeletons).toHaveLength(3);
   });
 
   it('renders feedback title and message when provided', () => {
diff --git a/src/components/dashboard/aluno/workout-editor.test.tsx b/src/components/dashboard/aluno/workout-editor.test.tsx
index b1f9e9c5..13cea808 100644
--- a/src/components/dashboard/aluno/workout-editor.test.tsx
+++ b/src/components/dashboard/aluno/workout-editor.test.tsx
@@ -208,6 +208,6 @@ describe('WorkoutEditor', () => {
     mockUseWorkoutExercises.mockReturnValue({ ...defaultHookReturn, exercicios: exercises });
 
     render(<WorkoutEditor onSave={mockOnSave} treinoToEdit={null} onCancel={mockOnCancel} />);
-    expect(screen.getAllByTestId('exercise-row').length).toBe(2);
+    expect(screen.getAllByTestId('exercise-row')).toHaveLength(2);
   });
 });
diff --git a/src/components/dashboard/alunos/columns.test.tsx b/src/components/dashboard/alunos/columns.test.tsx
index c18a2743..48a67ec8 100644
--- a/src/components/dashboard/alunos/columns.test.tsx
+++ b/src/components/dashboard/alunos/columns.test.tsx
@@ -103,7 +103,7 @@ describe('columns', () => {
 
   it('returns an array of column definitions', () => {
     expect(Array.isArray(columnDefs)).toBe(true);
-    expect(columnDefs.length).toBe(6);
+    expect(columnDefs).toHaveLength(6);
   });
 
   it('has photo column with accessorKey fotoUrl', () => {
diff --git a/src/components/ui/circular-progress.test.tsx b/src/components/ui/circular-progress.test.tsx
index 8368908d..cc11ec36 100644
--- a/src/components/ui/circular-progress.test.tsx
+++ b/src/components/ui/circular-progress.test.tsx
@@ -12,7 +12,7 @@ describe('CircularProgress', () => {
   it('renders SVG circles', () => {
     const { container } = render(<CircularProgress value={75} />);
     const circles = container.querySelectorAll('circle');
-    expect(circles.length).toBe(2);
+    expect(circles).toHaveLength(2);
   });
 
   it('displays value when showValue is true', () => {
diff --git a/src/lib/exercise-options.test.ts b/src/lib/exercise-options.test.ts
index 66ee2a1e..42e1e3d1 100644
--- a/src/lib/exercise-options.test.ts
+++ b/src/lib/exercise-options.test.ts
@@ -10,11 +10,11 @@ import { EXERCICIOS_POR_GRUPO } from './constants';
 describe('exerciciosOptions', () => {
   it('is a non-empty array', () => {
     expect(Array.isArray(exerciciosOptions)).toBe(true);
-    expect(exerciciosOptions.length).toBeGreaterThan(0);
+    expect(exerciciosOptions.length).toBeGreaterThanOrEqual(1);
   });
 
   it('has the same number of groups as EXERCICIOS_POR_GRUPO', () => {
-    expect(exerciciosOptions.length).toBe(EXERCICIOS_POR_GRUPO.length);
+    expect(exerciciosOptions).toHaveLength(EXERCICIOS_POR_GRUPO.length);
   });
 
   it('each entry has a label matching the group name and a non-empty options array', () => {
@@ -30,11 +30,11 @@ describe('exerciciosOptions', () => {
     for (const group of exerciciosOptions) {
       for (const opt of group.options) {
         expect(typeof opt.value).toBe('string');
-        expect(opt.value.length).toBeGreaterThan(0);
+        expect(opt.value.length).toBeGreaterThanOrEqual(1);
         expect(typeof opt.label).toBe('string');
-        expect(opt.label.length).toBeGreaterThan(0);
+        expect(opt.label.length).toBeGreaterThanOrEqual(1);
         expect(Array.isArray(opt.keywords)).toBe(true);
-        expect(opt.keywords.length).toBeGreaterThan(0);
+        expect(opt.keywords.length).toBeGreaterThanOrEqual(1);
       }
     }
   });
@@ -43,12 +43,12 @@ describe('exerciciosOptions', () => {
 describe('flatExerciciosOptions', () => {
   it('is a non-empty array', () => {
     expect(Array.isArray(flatExerciciosOptions)).toBe(true);
-    expect(flatExerciciosOptions.length).toBeGreaterThan(0);
+    expect(flatExerciciosOptions.length).toBeGreaterThanOrEqual(1);
   });
 
   it('contains the total count of all exercises across groups', () => {
     const totalExercises = EXERCICIOS_POR_GRUPO.reduce((sum, g) => sum + g.exercicios.length, 0);
-    expect(flatExerciciosOptions.length).toBe(totalExercises);
+    expect(flatExerciciosOptions).toHaveLength(totalExercises);
   });
 
   it('each entry has value, label, and description', () => {
@@ -105,7 +105,7 @@ describe('DEFAULT_EXERCISE', () => {
 
   it('has repeticoes as a non-empty string', () => {
     expect(typeof DEFAULT_EXERCISE.repeticoes).toBe('string');
-    expect(DEFAULT_EXERCISE.repeticoes.length).toBeGreaterThan(0);
+    expect(DEFAULT_EXERCISE.repeticoes.length).toBeGreaterThanOrEqual(1);
   });
 });