Formulas Reference
All pricing calculations used in Tillage quotes and invoices.
Line Item Calculations
Base Cost
The fundamental cost before any adjustments.
Base Cost = Quantity × Unit Price
Example:
- Quantity: 10 hours
- Unit Price: $150/hour
- Base Cost: 10 × $150 = $1,500
With Variance
Base cost adjusted for risk/uncertainty.
With Variance = Base Cost × (1 + Variance%)
Example:
- Base Cost: $1,500
- Variance: 20%
- With Variance: $1,500 × 1.20 = $1,800
Line Total (Final)
After applying profit margin.
Line Total = With Variance × (1 + Profit Margin%)
Example:
- With Variance: $1,800
- Profit Margin: 15%
- Line Total: $1,800 × 1.15 = $2,070
Complete Formula
Line Total = Quantity × Unit Price × (1 + Variance%) × (1 + Profit Margin%)
Full Example:
- Quantity: 10 hours
- Unit Price: $150
- Variance: 20%
- Profit Margin: 15%
Line Total = 10 × $150 × 1.20 × 1.15 = $2,070
Quote Calculations
Subtotal
Sum of all line item totals.
Subtotal = Σ (Line Total for each item)
Example:
- Line Item 1: $2,070
- Line Item 2: $3,450
- Line Item 3: $1,380
- Subtotal: $6,900
Discount Amount
#### Percentage Discount
Discount = Subtotal × (Discount Percentage / 100)
Example:
- Subtotal: $6,900
- Discount: 10%
- Discount Amount: $6,900 × 0.10 = $690
#### Fixed Discount
Discount = Fixed Amount (capped at Subtotal)
Example:
- Subtotal: $6,900
- Fixed Discount: $500
- Discount Amount: $500
Quote Total
Quote Total = Subtotal - Discount
Example:
- Subtotal: $6,900
- Discount: $690
- Quote Total: $6,900 - $690 = $6,210
With Tax (if applicable)
Tax Amount = (Subtotal - Discount) × Tax Rate
Total with Tax = (Subtotal - Discount) + Tax Amount
Example:
- Pre-tax Total: $6,210
- Tax Rate: 8%
- Tax: $6,210 × 0.08 = $496.80
- Final Total: $6,210 + $496.80 = $6,706.80
Payment Processing Fees
Credit Card (Stripe)
Card Fee = (Payment Amount × 0.029) + $0.30
Example:
- Payment: $5,000
- Fee: ($5,000 × 0.029) + $0.30 = $145.30
ACH Bank Transfer (Stripe)
ACH Fee = min(Payment Amount × 0.008, $5.00)
Example:
- Payment: $5,000
- Fee: min($5,000 × 0.008, $5) = min($40, $5) = $5.00
- Payment: $500
- Fee: min($500 × 0.008, $5) = min($4, $5) = $4.00
Platform Fee (Free Plan)
Platform Fee = Payment Amount × 0.01
Example:
- Payment: $5,000
- Platform Fee: $5,000 × 0.01 = $50
Net Amount Received
#### Free Plan (Card)
Net = Payment - Card Fee - Platform Fee
Example:
- Payment: $5,000
- Card Fee: $145.30
- Platform Fee: $50
- Net: $5,000 - $145.30 - $50 = $4,804.70
#### Free Plan (ACH)
Net = Payment - ACH Fee - Platform Fee
Example:
- Payment: $5,000
- ACH Fee: $5
- Platform Fee: $50
- Net: $5,000 - $5 - $50 = $4,945.00
#### Premium Plan (Card)
Net = Payment - Card Fee
Example:
- Payment: $5,000
- Card Fee: $145.30
- Net: $5,000 - $145.30 = $4,854.70
#### Premium Plan (ACH)
Net = Payment - ACH Fee
Example:
- Payment: $5,000
- ACH Fee: $5
- Net: $5,000 - $5 = $4,995.00
Convenience Fees
Percentage-Based
Convenience Fee = Invoice Amount × Fee Rate
Client Pays = Invoice Amount + Convenience Fee
Example:
- Invoice: $5,000
- Fee Rate: 3%
- Convenience Fee: $5,000 × 0.03 = $150
- Client Pays: $5,150
Fixed Amount
Convenience Fee = Fixed Fee Amount
Client Pays = Invoice Amount + Convenience Fee
Example:
- Invoice: $5,000
- Fixed Fee: $10
- Client Pays: $5,010
Payment Schedule Calculations
Percentage-Based Milestones
Milestone Amount = Quote Total × Milestone Percentage
Example:
- Quote Total: $10,000
- Deposit (50%): $10,000 × 0.50 = $5,000
- Final (50%): $10,000 × 0.50 = $5,000
Equal Installments
Installment Amount = Quote Total / Number of Installments
Example:
- Quote Total: $12,000
- Installments: 4
- Each Payment: $12,000 / 4 = $3,000
Breakeven Calculations
Premium vs Free Breakeven
Breakeven Volume = Premium Price / Platform Fee Rate
Example:
- Premium: $49/month
- Platform Fee: 1%
- Breakeven: $49 / 0.01 = $4,900/month
Premium Savings Above Breakeven
Monthly Savings = (Monthly Volume × 0.01) - $49
Example:
- Monthly Volume: $10,000
- Free Plan Fee: $10,000 × 0.01 = $100
- Premium Cost: $49
- Savings: $100 - $49 = $51/month
Variance Recommendations
| Risk Level | Variance Range | Use Case |
|---|---|---|
| Low | 5-10% | Repeat projects, clear scope |
| Standard | 10-15% | Typical projects |
| Moderate | 15-20% | New clients, some unknowns |
| High | 20-30% | Complex requirements |
| Very High | 30-50% | Experimental, unclear scope |
Quick Reference Table
| Calculation | Formula |
|---|---|
| Base Cost | Qty × Price |
| With Variance | Base × (1 + Var%) |
| Line Total | WithVar × (1 + Margin%) |
| Quote Total | Σ Lines - Discount |
| Card Fee | Amount × 2.9% + $0.30 |
| ACH Fee | min(Amount × 0.8%, $5) |
| Platform Fee | Amount × 1% (Free only) |
Related: Profitability Features | Variance Buffers Guide | Glossary