The loan calculator is the most-used tool ahead of a borrowing decision, yet many consumers run it without grasping what it shows and what it leaves out. The gap between the nominal rate entered in a simulator and the official APR on a personalised SECCI can run 4-5 percentage points, which on a 47,500 lei loan over 5 years means a 3,280 lei difference in total cost. The guide below explains the formula, what a standard simulator can and cannot calculate, and how to read the results.
Figures here follow GEO 50/2010 and the NBR average rates for new consumer loans published in June 2026.
Quick answer
Monthly payment formula: M = P × (r × (1+r)^n) / ((1+r)^n − 1).
Nominal interest doesn't include fees. APR includes everything.
Typical APR vs nominal gap on 2026 consumer loans: 1-4 percentage points.
A standard calculator estimates the payment and approximate cost; the official SECCI gives the exact figures.
Use our calculator for a quick comparison of 2-3 offers.
The mathematical formula explained
For a loan with equal payments (annuities), the standard type for consumer credit and mortgages:
M = P × (r × (1+r)^n) / ((1+r)^n − 1)
Where:
• M = monthly payment
• P = principal borrowed (amount requested)
• r = monthly interest rate = annual rate / 12 (as a decimal, 0.00733 for 8.79% annual)
• n = total number of months
Example for a 47,500 lei loan over 60 months at 8.79% nominal annual rate:
r = 0.0879 / 12 = 0.007325. (1+r)^60 = 1.549. M = 47,500 × (0.007325 × 1.549) / (1.549 − 1) = 47,500 × 0.01135 / 0.549 = 982 lei per month.
Total to pay over 60 months: 60 × 982 = 58,920 lei. Principal recovered 47,500 lei, total interest 11,420 lei. This figure is computed on the nominal rate, without fees.
APR vs nominal rate, the real gap
APR adds, on top of interest, every mandatory fee:
Origination fee: typically 1-3% of the borrowed amount, paid once at signing.
Monthly administration fee: typically 0.1-0.5% of the outstanding balance, paid with each instalment.
Loan-linked insurance: if required for approval, it enters the APR. If optional and you accept it, the cost goes into your budget separately, not into the APR.
For the same 47,500 lei loan over 60 months at 8.79% nominal, with a 2% origination fee (950 lei one-off) and a 0.3% monthly admin fee (around 140 lei per month, declining with the balance):
Resulting APR: roughly 11.18% (versus 8.79% nominal). Total cost: 13,620 lei versus 11,420 lei on nominal alone. The fee-driven gap: 2,200 lei.
Steps in our calculator
On /en/calculatoare you find the loan calculator. The process takes 4 steps.
Step 1, amount and term: enter the amount you need and the term in months (we suggest 60-84 months for consumer credit, 240-360 for a mortgage).
Step 2, loan type: pick between personal loan (annual fixed), mortgage (IRCC variable or fixed), car loan, or other.
Step 3, nominal rate: enter the offer's rate or, for a ballpark estimate, leave the market default (9.45% for personal loans, 7.65% for 5-year fixed mortgages, both June 2026).
Step 4, optional, fees: if you know the origination and admin fees, enter them for an APR estimate. If not, the calculator shows only the payment on nominal interest with a note that the real APR will run 1-4 percentage points higher.
The result shows the monthly payment, total cumulative interest, estimated APR (if you entered fees), and a year-by-year payment chart.
How to compare offers properly with the calculator
The key step in any comparison is using the same inputs (amount, term) across all offers and entering each offer's specific fees separately. The resulting table helps you see which is cheaper cumulatively.
Here is a simulated comparison of 3 offers on 47,500 lei over 60 months:
| Lender | Rate | Origination | Admin | Estimated APR | Monthly | Total cost |
|---|---|---|---|---|---|---|
| Bank A | 8.79% | 1.2% | 0.18% | 9.42% | 981 lei | 11,355 lei |
| Bank B | 8.79% | 2.8% | 0.42% | 11.73% | 1,040 lei | 14,875 lei |
| Bank C | 9.15% | 0.8% | 0.12% | 9.68% | 989 lei | 11,840 lei |
Key observation: the same nominal rate (A vs B) drives completely different cumulative costs because of the fees. Bank A is cheaper even though its nominal rate matches B. Comparing on APR clears it up immediately.
Case study: Andrei, Iași, May 2026
Bogdan Băicu, financial journalist: "A reader, Andrei, 39, engineer at a car-industry firm in Iași, wanted to refinance a personal loan with 47,500 lei outstanding and 38 months left at 11.73% APR. He used our calculator to compare 3 refinancing offers from BCR, BT, and ING. All three had similar nominal rates of 8.9-9.2%, but fee differences pushed total costs apart by 1,940 lei across the remaining 38 months.
"Andrei chose ING with a final APR of 9.68% and a total cost of 41,620 lei over the new term. Keeping the old loan would have meant 47,380 lei in remaining costs. Net refinancing saving: 5,760 lei minus the early repayment fee of 475 lei, total 5,285 lei net. The lesson for readers: running the standard tool while entering fees accurately separates an informed decision from a lucky one. 15 minutes at the calculator can mean 5,000+ lei saved across a 3-year horizon."
Common mistakes when using the calculator
First common error: entering the nominal rate and treating the result as APR. For an honest buyer-side comparison, you need the offer's APR, which includes the fees.
Second: comparing without holding the term constant. Two offers with similar monthly payments but different terms (48 vs 60 months) have different total costs, and the monthly comparison is meaningless without the term context.
Third: ignoring optional insurance. If you accept it at signing, its monthly cost (40-150 lei) lands in your budget separately, while the official APR doesn't include it (since it's optional).
Frequently asked questions
Does your calculator use the standard banking formula? Yes, the annuity formula that is the standard in GEO 50/2010 and EU Directive 2008/48/EC.
Why is your calculator lower than the bank's official one? Because the bank officially includes specific fees in its number. Our calculator is a generic tool; the bank's is personalised to your profile and the exact product.
Can I use it for a variable-rate loan? Estimate at the current rate, yes. For a future projection, no, because the rate changes monthly (ROBOR) or quarterly (IRCC).
Can the bank refuse to give me the SECCI? No. Under GEO 50/2010 art. 11, the personalised SECCI is an absolute right. Written request, reply in 1-3 days.
What amount should I ask the calculation on? We suggest a SECCI request for the exact amount and term you need, not a round ballpark. The APR varies across specific amounts and terms.
Related
• Loan calculator
• What is APR explained
• The SECCI standard sheet
• Compare personal loans
Editor's note: "The loan calculator is a handy tool for a quick orientation, but it doesn't replace the personalised SECCI. General guidance: use the calculator for an initial screen across 3-5 preliminary offers, then request the SECCI for the top 2-3, run the final comparison on the official numbers, and decide after 30 minutes of analysis. Those 30 minutes can mean thousands of lei saved over a 3-5 year horizon."