Trial balance and error detective
See a real trial balance, then diagnose errors and explain why some don't break the equality of debits and credits.
Sandbox
Self-check practice on this device: your entries autosave locally. The sandbox isn't graded for mastery — use the graded practice below for that.
Brightside Services (worked example)
Period Jan 1, 2026 – Jan 31, 2026 · accrual basis · USD
| Account | Debit | Credit |
|---|---|---|
| 1000 · Cash | $8,600.00 | |
| 1100 · Accounts Receivable | $1,500.00 | |
| 1300 · Supplies | $150.00 | |
| 1400 · Prepaid Insurance | $1,100.00 | |
| 1500 · Equipment | $2,000.00 | |
| 1510 · Accumulated Depreciation – Equipment | $100.00 | |
| 2000 · Accounts Payable | $100.00 | |
| 2100 · Wages Payable | $250.00 | |
| 3000 · Owner Capital | $10,000.00 | |
| 4000 · Service Revenue | $4,000.00 | |
| 6000 · Rent Expense | $500.00 | |
| 6100 · Wages Expense | $250.00 | |
| 6300 · Supplies Expense | $150.00 | |
| 6400 · Insurance Expense | $100.00 | |
| 6500 · Depreciation Expense | $100.00 | |
| Totals ✓ | $14,450.00 | $14,450.00 |
Equal totals show every entry was posted with equal sides. They don't prove the right accounts were used.
Graded practice
Item 1 of 10
Freeeasy
Error detective: error of omission?
A $900.00 supplier bill for repairs was never entered in the books. Identify the type of error, whether the trial balance will still balance, and the difference between total debits and total credits (enter 0 if it balances).