Does the calculator open with Seal and Mazda3 already selected?

Yes. Open prefilled calculator loads both vehicles on the home page with your default region.

Why Mazda3 G20 Evolve specifically?

It is the entry-level Mazda3 variant in my vehicle database — a clear baseline for the petrol sedan segment.

Is BYD Seal reliable in Australia?

Reliability is outside my TCO model. BYD offers a standard manufacturer warranty; check their Australian site for current terms.

Can I compare Seal against Corolla instead?

Yes — pick any petrol or hybrid vehicle from the dropdown once you are on the calculator page.

How does BYD Seal resale hold up?

I use a simplified residual fraction. Real BYD resale data in Australia is limited; treat the residual slider as a sensitivity lever.

Is this financial advice?

No. CarCostIQ is an educational comparison tool. Confirm taxes, incentives, and finance with qualified professionals.

BYD Seal vs Mazda3 G20 Evolve — 5-Year Cost Comparison (Australia)

BYD Seal versus Mazda3 G20 Evolve: a modern EV sedan against a refined petrol sedan. The Seal is BYD's sportier offering with a ~$46,990 MSRP, while the Mazda3 sedan sits at ~$31,410 — a notable upfront gap. This comparison helps you see whether energy and maintenance savings close that gap over five years.

For sedan shoppers weighing a premium EV experience against a well-known, affordable petrol option — particularly if you drive enough km to let energy savings accumulate.

At a glance

BYD Seal

MSRP: $46,990
Efficiency: 15.6 kWh/100 km
Class: Sedan

Petrol

Mazda3 G20 Evolve

MSRP: $31,410
Efficiency: 5.9 L/100 km
Class: Sedan

Purchase price gap: $15,580 higher for EV

BYD Seal

$46,990

G20 Evolve

$31,410

MSRP only — run the calculator to see the full TCO picture including energy, insurance, and resale.

Quick trade-off summary

No fixed winner here — outcomes depend on your km, tariffs, and any assumptions you change. Typical tensions:

The ~$15.6k MSRP difference is the central tension. The Seal needs strong km and favourable electricity rates to close this gap on pure cost.
Mazda3's 5.9 L/100 km is competitive for petrol; the Seal's 15.6 kWh/100 km is efficient for EV — but the per-km cost difference depends on your energy prices.
Resale uncertainty: BYD is newer in the Australian market; Mazda3 has decades of resale history.

Who this comparison is for

Daily commuter: 12–20k km/year in city traffic where the EV's efficiency advantage is most consistent.
Budget-conscious buyer: Mazda3's lower entry point matters; use TCO to check if total cost flips over five years.
Tech-forward buyer: BYD Seal offers newer tech; confirm whether the cost premium pays back in your usage pattern.
First-car buyer: Lower purchase price vs lower running cost — the calculator quantifies this trade-off.

Key assumptions behind the comparison

Five-year ownership horizon with standard CarCostIQ defaults.
BYD Seal at 15.6 kWh/100 km; Mazda3 G20 at 5.9 L/100 km — both from Green Vehicle Guide.
Insurance and maintenance use flat annual defaults; override with your quotes for accuracy.
Residual fractions are simplified — BYD resale data in Australia is still limited.

When the EV is more likely to come out ahead

Annual km above ~15k combined with home charging at off-peak or solar rates.
You hold the car for the full five years, giving compounding savings more runway.
Petrol prices stay at or above current levels in your state.

When the petrol / hybrid side may still win on cash cost

Annual km below ~10k — the Mazda3's lower MSRP dominates when fuel spend is minimal.
You rely heavily on public DC charging, raising effective EV c/kWh.
You prefer the certainty of Mazda's long-established Australian resale market.

Cost drivers to watch

Annual km — scales both energy lines but the per-km gap matters.
Electricity c/kWh vs petrol c/L — the conversion rate between the two energy costs.
MSRP gap (~$15.6k) — the number running costs need to offset.
Charging mix — home vs public changes the Seal's effective energy cost.
Residual value — newer brand vs established brand resale dynamics.

Frequently asked questions

Does the calculator open with Seal and Mazda3 already selected?: Yes. Open prefilled calculator loads both vehicles on the home page with your default region.
Why Mazda3 G20 Evolve specifically?: It is the entry-level Mazda3 variant in my vehicle database — a clear baseline for the petrol sedan segment.
Is BYD Seal reliable in Australia?: Reliability is outside my TCO model. BYD offers a standard manufacturer warranty; check their Australian site for current terms.
Can I compare Seal against Corolla instead?: Yes — pick any petrol or hybrid vehicle from the dropdown once you are on the calculator page.
How does BYD Seal resale hold up?: I use a simplified residual fraction. Real BYD resale data in Australia is limited; treat the residual slider as a sensitivity lever.
Is this financial advice?: No. CarCostIQ is an educational comparison tool. Confirm taxes, incentives, and finance with qualified professionals.

Run this comparison live

The link loads both vehicles and NSW on the home calculator. A short banner appears above the form so you can confirm the right models are there before changing km, tariffs, or charging mix. The same setup carries through to the result page and any share link you copy.

What you should see next

1. A banner above the calculator confirming the selected pair and region.
2. The same vehicles carried into the result page before you copy or share the link.

Open prefilled calculator View 5-year result now Read methodology

Based on current reference pricing and published methodology. Data last reviewed: 2026-05-27. Estimates only — not financial advice.