Duolingo, Inc.

0001001 - Document - Cover Page

1002004 - Statement - CONSOLIDATED BALANCE SHEETS (Parenthetical)

1003005 - Statement - CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS

1004006 - Statement - CONSOLIDATED STATEMENTS OF CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS??? EQUITY (DEFICIT)

1005007 - Statement - CONSOLIDATED STATEMENTS OF CASH FLOWS

0002002 - Document - Audit Information

2101101 - Disclosure - DESCRIPTION OF THE BUSINESS AND BASIS OF PRESENTATION

2103102 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES

2109103 - Disclosure - REVENUE

2115104 - Disclosure - PROPERTY and EQUIPMENT, net

2119105 - Disclosure - CAPITALIZED SOFTWARE, net

2124106 - Disclosure - LEASES

2129107 - Disclosure - INCOME TAXES

2135108 - Disclosure - CONVERTIBLE PREFERRED STOCK

2139109 - Disclosure - STOCK-BASED COMPENSATION

2148110 - Disclosure - COMMITMENTS AND CONTINGENCIES

2149111 - Disclosure - ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES

2152112 - Disclosure - EMPLOYEE BENEFIT PLAN

2154113 - Disclosure - EARNINGS PER SHARE

2204201 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)

2305301 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Tables)

2310302 - Disclosure - REVENUE (Tables)

2316303 - Disclosure - PROPERTY and EQUIPMENT, net (Tables)

2320304 - Disclosure - CAPITALIZED SOFTWARE, net (Tables)

2325305 - Disclosure - LEASES (Tables)

2330306 - Disclosure - INCOME TAXES (Tables)

2336307 - Disclosure - CONVERTIBLE PREFERRED STOCK (Tables)

2340308 - Disclosure - STOCK-BASED COMPENSATION (Tables)

2350309 - Disclosure - ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES (Tables)

2355310 - Disclosure - EARNINGS PER SHARE (Tables)

2402401 - Disclosure - DESCRIPTION OF THE BUSINESS AND BASIS OF PRESENTATION (Details)

2406402 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Cash and Cash Equivalents (Details)

2407403 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Narrative (Details)

2408404 - Disclosure - SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Schedule of Useful Life (Details)

2411405 - Disclosure - REVENUE - Disaggregation of Revenue (Details)

2412406 - Disclosure - REVENUE - Revenue by Geographic Area (Details)

2413407 - Disclosure - REVENUE - Deferred Revenue Rollforward (Details)

2414408 - Disclosure - REVENUE - Narrative (Details)

2417409 - Disclosure - PROPERTY and EQUIPMENT, net - Summary (Details)

2418410 - Disclosure - PROPERTY and EQUIPMENT, net - Narrative (Details)

2421411 - Disclosure - CAPITALIZED SOFTWARE, net - Capitalized Software (Details)

2422412 - Disclosure - CAPITALIZED SOFTWARE, net - Narrative (Details)

2423413 - Disclosure - CAPITALIZED SOFTWARE, net - Schedule of Capitalized Software Amortization Expense (Details)

2426414 - Disclosure - LEASES - Narrative (Details)

2427415 - Disclosure - LEASES - Components of Lease Cost (Details)

2428416 - Disclosure - LEASES - Future Minimum Rental Payment (Details)

2431417 - Disclosure - INCOME TAXES - Narrative (Details)

2432418 - Disclosure - INCOME TAXES - Deferred Tax Assets and Liabilities (Details)

2433419 - Disclosure - INCOME TAXES - Valuation Allowance (Details)

2434420 - Disclosure - INCOME TAXES - Effective Income Tax Rate Reconciliation (Details)

2437421 - Disclosure - CONVERTIBLE PREFERRED STOCK - Schedule of Convertible Preferred Stock (Details)

2438422 - Disclosure - CONVERTIBLE PREFERRED STOCK - Narrative (Details)

2441423 - Disclosure - STOCK-BASED COMPENSATION - Narrative (Details)

2442424 - Disclosure - STOCK-BASED COMPENSATION - Stock Option Activity (Details)

2443425 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Payment Pricing Model (Details)

2444426 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Restricted Stock Unit Activity (Details)

2445427 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Payment Award (Details)

2446428 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Income Statement Location for Compensation Expense (Details)

2447429 - Disclosure - STOCK-BASED COMPENSATION - Schedule of Weighted Average Pricing Model (Details)

2451430 - Disclosure - ACCRUED EXPENSES AND OTHER CURRENT LIABILITIES (Details)

2453431 - Disclosure - EMPLOYEE BENEFIT PLAN (Details)

2456432 - Disclosure - EARNINGS PER SHARE - Schedule of Earnings Per Share, Basic and Diluted (Details)

2457433 - Disclosure - EARNINGS PER SHARE - Schedule of Antidilutive Securities (Details)

2458434 - Disclosure - EARNINGS PER SHARE - Narrative (Details)

1001003 - Statement - CONSOLIDATED BALANCE SHEETS