This manual explains how to correctly create and validate calculation formulas in FirstBIT software, following 1C calculation logic.
It is intended for HR, Payroll, Finance, and ERP users who configure salary, allowance, overtime, or commission calculations.
When creating formulas in FirstBIT software, always follow these core principles:
Period-based calculation
All calculations are performed for a defined period (usually one month).
Proportional accrual
Amounts must be calculated proportionally based on:
days worked, or
hours worked.
Consistency of units
Day-based parameters must be used only with days.
Hour-based parameters must be used only with hours.
Amount-based parameters must not be mixed with time units without clear proration logic.
Separation of norms and actuals
Norm values define the standard (Norm Days / Norm Hours).
Actual values reflect real work (Days Worked / Hours Worked).
No double counting
A formula must never reduce or increase the same amount twice (e.g. by both absence days and absence hours).
| Parameter | Description | Correct Use | Do NOT Use When |
|---|---|---|---|
| Absence Days | Number of absent working days | Reducing day-based payments | Calculating hourly salary |
| Absence Hours | Number of absent hours | Reducing hour-based payments | Calculating day-based salary |
| Days In Period | Total days in the period | Denominator for proportional logic | Replacing Norm Days without reason |
| Days Worked | Actual worked days | Monthly salary proration | Hour-based formulas |
| Fixed Amount | Fixed value | Allowances, bonuses, deductions | Without proration logic if required |
| Hours Worked | Actual worked hours | Hourly salary calculation | Day-based salary |
| Hours Worked by Jobs | Hours per job/project | Multi-job or project payroll | Simple single-job payroll |
| Norm Days | Standard working days | Monthly salary base | Hour-based calculations |
| Norm Days by Schedule | Norm days per employee schedule | Shift / flexible schedules | Fixed schedules |
| Norm Hours | Standard working hours | Hourly & overtime base | Day-based formulas |
| Overtime Hours | Hours beyond norm | Overtime calculation | Regular salary |
| Sales Amount | Total sales value | Turnover-based commission | Margin-based commission |
| Sales Margin | Profit from sales | Margin-based commission | Turnover-based commission |
| Tariff | Salary rate (daily/hourly/monthly) | Base of all calculations | When unit does not match formula |
Tariff × Days Worked / Norm Days
Tariff × Hours Worked
Tariff × (Norm Days − Absence Days) / Norm Days
Tariff × (Norm Hours − Absence Hours)
Tariff × Overtime Hours × Overtime Coefficient
Fixed Amount × Days Worked / Norm Days
Sales Amount × Commission Rate
or
Sales Margin × Commission Rate
Incorrect:
Tariff × Hours Worked / Norm Days
Correct:
Use hours with Norm Hours, days with Norm Days.
This leads to double reduction.
Choose one unit only, based on how the salary is calculated.
This may distort salary calculations.
Use Norm Days unless there is a documented business reason.
Example:
Hourly tariff × Days Worked
Always match tariff unit with calculation unit.
This may overpay or underpay in partial months.
Clearly define whether the amount should be prorated.
Use this checklist:
Is this calculation based on days, hours, or amount?
Days → Days Worked / Norm Days
Hours → Hours Worked / Norm Hours
Are absences deducted only once?
Are days/hours used correctly?
Employee joined mid-month
Employee had absences
Employee worked overtime
Full month → full tariff amount
Partial month → proportionally reduced amount
If the result matches expectations, the formula is correct.
Correct formula creation in FirstBIT software requires:
strict adherence to 1C calculation logic;
consistent use of parameters;
careful validation before use.
Following this User Guide ensures:
accurate payroll and commission calculations;
predictable system behavior;
transparency for audit and reconciliation.
Thank you for being FIRSTBit customer!