Voyage Estimator
User Guide — Calculate TCE, voyage costs & profitability
Version 1.0 — April 20261. Overview
The TheCharterBox Voyage Estimator is a professional tool for calculating Time Charter Equivalent (TCE), total voyage costs, and voyage profitability. Designed for ship owners, charterers, brokers, and operators who need quick, accurate voyage economics.
The calculator runs entirely in your browser — results update instantly as you type. All bunker prices, exchange rates, and carbon prices are auto-fetched and cached daily.
Multi-Leg Voyages
Up to 5 voyage legs with auto-distance from a built-in 800+ port database.
Auto Bunker Prices
Live VLSFO and MGO prices from major bunker hubs — updated every 6 hours.
Canal Auto-Detection
Suez and Panama canal transits detected from route, with cost estimation.
ECA Fuel Switching
Automatic fuel switching when route enters Emission Control Areas.
Multi-Cargo Parcels
Split cargo across up to 3 parcels with different freight rates.
EU ETS Carbon Cost
Auto-calculated carbon cost for voyages calling EU/EEA ports.
Sensitivity Analysis
See how TCE changes with freight rate and bunker price variations.
Currency Switcher
View results in USD, EUR, or GBP with live exchange rates.
2. Getting Started
Access the Estimator
Visit www.thecharterbox.com/voyage-estimator/. No login required to use the calculator and see results.
Account Benefits
| Feature | Without Account | With Free Account |
|---|---|---|
| Use calculator & see results | ✅ | ✅ |
| Sensitivity analysis | ✅ | ✅ |
| Share via link | ✅ | ✅ |
| Print estimate | — | ✅ |
| Export PDF | — | ✅ |
| Save to account (max 20) | — | ✅ |
| Voyage comparison | — | ✅ |
| Email estimate | — | ✅ |
| Report issues | — | ✅ |
Register free at www.thecharterbox.com/register/
Single-Page Layout
All inputs are organised in collapsible sections. Work top to bottom: vessel details, route, consumption, costs. Results panel updates live on the right side.
3. Vessel Details
Define the vessel characteristics that drive cargo intake and tonnage-based costs.
Vessel Templates
Select a preset to auto-fill speed, consumption, and tonnage values for common vessel types.
| Preset | DWT | Use Case |
|---|---|---|
| Handysize | 28,000 | Small ports, flexible cargo |
| Supramax | 56,000 | Most common dry bulk size |
| Panamax | 75,000 | Coal, grain, larger bulk |
| Capesize | 180,000 | Iron ore, large coal cargoes |
Required Fields
| Field | Description |
|---|---|
| Vessel Name | Optional reference for PDF/save name |
| Deadweight (DWT) | Summer deadweight tonnage |
| Constants | Stores, water, crew effects (default 300 MT) |
| Bunker ROB on Arrival | Remaining bunkers on board, deducted from intake |
| Cargo Intake | Auto-calculated: DWT − Constants − ROB. Override allowed. |
| Gross Tonnage (GT) | For Panama Canal cost estimate |
| Net Tonnage (NT/SCNT) | For Suez Canal cost estimate |
4. Voyage Route
Build the voyage from port to port. Each leg can be tagged Laden or Ballast.
Adding Legs
- Click “+ Add Leg” to add a new voyage leg (up to 5 total).
- Type the From Port — autocomplete suggests matching ports from a database of 800+ commercial ports worldwide.
- Type the To Port — distance auto-calculates instantly using great circle + routing factor.
- Toggle Laden or Ballast for each leg.
- Set the Weather Factor % (default 5%) — added to sea days for sea state allowance.
Port Autocomplete
Type 2+ characters to see matching ports. Searches by port name, country, and code (e.g., “rotter” → Rotterdam, “ind” → Indian ports). Each entry shows port name, country, and code.
Auto-Distance
Distances are calculated using the Haversine formula plus a routing factor (1.10 to 1.30) based on the route geography. Suez and Panama canal routes add transit distance automatically.
Manual Port Entry
If a port isn’t in the database, type any custom name and enter the distance manually. The leg will still calculate correctly.
5. Speed & Consumption
Enter vessel speed and fuel consumption for laden, ballast, and port states. Vessel templates pre-fill typical values.
| State | Fields |
|---|---|
| Laden | Speed (knots), IFO MT/day, MDO MT/day |
| Ballast | Speed (knots), IFO MT/day, MDO MT/day |
| In Port | IFO MT/day, MDO MT/day (typically auxiliary/generators) |
6. Port Days & Canal Transit
Port Days
| Field | Description |
|---|---|
| Loading Port Days | Total days at loading port(s) |
| Discharge Port Days | Total days at discharge port(s) |
| Extra / Canal Days | Suez/Panama transit time, waiting, or any other delays |
Canal Transit Auto-Detection
The estimator auto-detects when a route logically passes through Suez or Panama based on the port regions of each leg.
| Canal | Auto-Detected For |
|---|---|
| Suez | Europe/Med ↔ Asia, Middle East, East Africa |
| Panama | US East ↔ US West, EC South America ↔ Pacific |
| Cape (no canal) | Capesize vessels too large for Suez |
Canal Cost Estimate
Estimated based on vessel DWT and direction (laden/ballast). Suez uses SCNT, Panama uses GT. Approximate ranges:
| Vessel | Suez (USD) | Panama (USD) |
|---|---|---|
| Handysize | $150,000–200,000 | $80,000–120,000 |
| Supramax | $250,000–300,000 | $150,000–200,000 |
| Panamax | $300,000–350,000 | $250,000–400,000 |
7. Bunker Prices
Bunker prices are auto-fetched from OilPriceAPI every 6 hours and cached server-side. Prices are global Singapore benchmarks — the industry’s primary bunker pricing hub.
Price Source
All bunker prices are sourced from OilPriceAPI’s Singapore benchmark — the world’s largest bunkering port by volume. Prices are indicative and may differ from your actual port of supply. Always verify with your bunker supplier before fixing.
| Fuel Code | Plugin Field | Description |
|---|---|---|
| VLSFO_USD | IFO Price (when VLSFO selected) | Very Low Sulphur Fuel Oil, 0.5% sulphur |
| HFO_380_USD | IFO Price (when HSFO selected) | High Sulphur Fuel Oil, 3.5% (scrubber vessels) |
| MGO_05S_USD | MDO/MGO Price | Marine Gas Oil, 0.5% sulphur |
Auto-Update Behaviour
- Server fetches latest VLSFO, MGO, and HFO prices every 6 hours from OilPriceAPI.
- Prices cached as WordPress transients (24-hour TTL).
- Calculator pre-fills both fields with current cached prices.
- “≈ auto” badge shown next to auto-populated prices.
- User can override either price — “auto” badge disappears on manual edit.
Historical Sparkline
Below each bunker price field, a small sparkline chart shows the price trend over recent days. Tap or hover to see specific date and price values. The sparkline builds over time as prices are cached daily.
8. ECA Fuel Switching
Emission Control Areas (ECAs) require vessels to burn cleaner, more expensive fuel (MGO 0.1% sulphur) within zone boundaries.
ECA Zones Detected
| Zone | Region |
|---|---|
| North Sea / English Channel | NW Europe |
| Baltic Sea | Baltic states, Scandinavia |
| North America | 200 NM from US/Canada coasts |
| US Caribbean | Puerto Rico, USVI |
Fields
| Field | Description |
|---|---|
| Vessel has Scrubber | If Yes, no fuel switching needed (vessel can burn HSFO in ECAs) |
| ECA Fuel Type | MGO or ULSFO |
| ECA Fuel Price | Auto-synced from MDO/MGO Price field |
| ECA Consumption (Laden/Ballast) | MT/day burned in ECA zones |
Calculation
The estimator splits each voyage leg into ECA and non-ECA portions. The ECA portion uses MGO consumption and price; the non-ECA portion uses normal IFO. The “ECA Premium” line in the breakdown shows the additional cost compared to burning IFO throughout.
9. Revenue & Costs
Cargo Parcels
Support for 1 to 3 cargo parcels with different freight rates. Common in Handysize/Supramax trades carrying multiple grades of cargo.
| Field | Description |
|---|---|
| Parcel Name | Optional label, e.g. “Steel coils”, “Pig iron” |
| Quantity | MT — must not exceed total cargo intake |
| Freight Rate | $/MT for this parcel |
| Commission | % per parcel (default 3.75%) |
Ballast Bonus
Lump sum payment from charterer to compensate for vessel repositioning. Add the BB amount and BB commission separately.
Port Disbursements
Total Port DA (Disbursement Account) for loading and discharging ports — covers port dues, pilotage, towage, agency fees, etc.
Other Misc Costs
Any other voyage-specific costs not captured elsewhere — special inspections, security escorts, towage, etc.
10. TC Hire Comparison
Compare voyage charter results against a time charter hire rate to decide which is more profitable.
Fields
| Field | Description |
|---|---|
| Daily TC Hire Rate | Market or offered TC rate ($/day) |
| TC Duration | Defaults to voyage duration, or set custom |
| TC Commission | % (default 3.75%) |
Comparison Output
Shows side-by-side: voyage daily earning vs TC daily earning, total income for each, and a recommendation indicating which is more profitable. The break-even TC rate is also displayed.
11. Carbon / EU ETS
Estimate the EU Emissions Trading System cost for voyages calling at EU/EEA ports.
EU ETS Rules (Simplified)
| Voyage Type | ETS Liability |
|---|---|
| EU ↔ EU | 100% of emissions |
| EU ↔ Non-EU | 50% of emissions |
| Non-EU ↔ Non-EU | 0% (not applicable) |
Auto-Detection
The estimator detects EU/EEA ports from the voyage legs and auto-sets the ETS scope. Manual override available.
Auto-Fetched Values
- EUA Price — fetched from OilPriceAPI in EUR/tonne CO₂.
- EUR/USD Rate — fetched from Frankfurter API daily.
- Both can be manually overridden if needed.
Calculation
The ETS cost is added to total voyage cost and reduces TCE accordingly.
12. Results & Sensitivity Analysis
Key Outputs
The Results panel shows the headline TCE prominently, followed by:
| Metric | Description |
|---|---|
| TCE ($/day) | The headline number — daily earning equivalent |
| Net Revenue | Gross revenue + BB minus all commissions |
| Total Voyage Cost | Bunkers + port DAs + canal + ETS + misc |
| Voyage Profit/Loss | Net revenue minus voyage cost (green if positive) |
| Total Voyage Days | Sea days + port days + extras |
| Bunker Consumption | Total IFO and MDO in MT |
Detailed Breakdown
P&L style table showing all revenue, all costs, and the final voyage result with TCE. Per-parcel rows for multi-cargo voyages.
Sensitivity Analysis
5×5 matrix showing TCE at different freight rate and bunker price levels (±10%, ±5%, base). Lets you instantly see how price changes affect profitability.
13. Save, Load & Compare
Saving (Logged-In Only)
- Click “Save Snapshot” — name auto-generated as “Vessel — Load Port → Discharge Port — Date”.
- Edit the name if desired and confirm.
- For existing estimates: choose “Update” or “Save as New”.
Loading
Click “Load” to see your saved estimates. Click any saved estimate to fully restore all settings — vessel, route, consumption, costs, and revenue inputs.
Voyage Comparison
Select 2 or 3 saved estimates and click “Compare” to see them side by side in a comparison table. Best TCE highlighted in green. Useful for evaluating different routes, vessel sizes, or market scenarios for the same cargo.
14. Export (PDF, Print, Share, Email)
Click “Print” or press Ctrl+P. A clean print stylesheet hides the inputs and shows only the results, ready for a paper copy or PDF print.
PDF Export
Professional branded document containing vessel details, full route, key results, detailed breakdown, bunker summary, and TC hire comparison.
File: voyage-estimate-[YYYY-MM-DD].pdf
Share Link
Generates a shareable URL with all current inputs encoded. Recipients see the same estimate when they open the link. No login required to share or open.
Email Estimate
Send the estimate directly to one or more email addresses (max 5 recipients). PDF attachment optional. Add a personal message before sending.
15. Reporting Issues
Click “Report Issue” in the header (logged-in only). Name and email pre-filled from your profile. Select issue type (Bug, Feature Request, Other) and describe the issue.
Reports go to [email protected].