We ran the exact same search on Google Flights, Skyscanner, Kayak, Momondo and Kiwi.com using the same dates and currency. On a short, cheap hop you'd expect them to agree. They didn't. Here's what we found.
You'd expect five tools to agree on a two-and-a-half-hour hop. They didn't. Kayak and Momondo were cheapest at S$187 (a Scoot-out, TransNusa-back combo), Google was S$235, and Skyscanner was S$266, a spread of nearly 40% for the same nonstop trip. Every one of those cheap fares is carry-on only; a full-service Garuda ticket with a bag was around S$289 to S$324. Kiwi.com's S$257 was competitive, but it's a reseller, so we rank it last. Prices change constantly, so treat this as a snapshot.
Ranked by the cheapest fare. Everything on this route is a nonstop, so the columns are the cheapest budget fare, the cheapest full-service fare with a bag, and the cheapest business-class seat. The badge under each tool shows how you book with it.
| Rank | Tool | Cheapest fare | Full-service, bag included | Cheapest business, direct |
|---|---|---|---|---|
| 1 |  Kayak Comparison site | S$187   Scoot out, TransNusa back nonstop, ~2h 50m each way | S$289  Garuda · bag included ~2h 35m | S$747 Garuda · nonstop ~2h 35m |
| 2 |  Momondo Comparison site | S$187 Scoot out, TransNusa back nonstop, ~2h 50m each way | S$289 Garuda · bag included ~2h 35m | S$747 Garuda · nonstop ~2h 35m |
| 3 |  Google Flights Comparison site | S$235  Jetstar out, Qantas back nonstop, ~2h 55m each way | S$300 Garuda · bag included ~2h 35m | S$747 Garuda · nonstop ~2h 35m |
| 4 |  Skyscanner Comparison site | S$266 Scoot out, Jetstar back nonstop, ~2h 50m each way | S$324 Garuda · bag included ~2h 35m | S$747 Garuda · nonstop ~2h 35m |
| 5 |  Kiwi.com Reseller | S$257 Nonstop each way · carry-on only ~2h 55m each way | S$391 Garuda · nonstop · bag included ~2h 35m | S$807 Garuda · nonstop ~2h 35m |
Scoot, Jetstar and TransNusa. A cabin bag and the seat, nothing else. A checked bag, a chosen seat and food are all paid extras.
Garuda (or Singapore Airlines). Pricier, but a checked bag, a seat and a meal are already in the fare, so add the bag before you compare.
A comparison site shows the fares and sends you to the airline or an agency to pay. A reseller like Kiwi.com takes your payment itself and adds its own fees, so it usually costs a little more.
What "Scoot out, TransNusa back" means: on a round trip these tools mix airlines, one carrier out and a different one home. Each leg is still a single nonstop flight; it's just two one-way tickets combined into one price. That's how the cheap fares are built: Kayak and Momondo paired a Scoot outbound with a TransNusa return to reach S$187; Google's cheapest was a Jetstar-out, Qantas-back combo at S$235; Skyscanner used Scoot out and Jetstar back. Same planes in the sky, priced differently.
The cheap fare is carry-on only. Every sub-S$270 fare here is a budget ticket with a cabin bag and nothing in the hold. A checked bag adds S$30 to S$50 each way, and paying at the airport costs more. A full-service Garuda ticket (S$289 to S$324) already includes a bag, so add your luggage before you compare, not after.
What business class costs here: the cheapest lie-flat-ish business seat was Garuda at about S$747 nonstop, and every comparison site showed the same fare. That's roughly four times the S$187 budget economy and about two and a half times the S$289 full-service economy. On a 2.5-hour hop that's a lot to pay for a wider seat and lounge access, but it's there if you want it. Kiwi sold the same Garuda business seat too, priced up at S$807.
Kayak and Momondo are owned by the same company and returned identical fares; we list both because people search for each. Kiwi.com's budget fare (S$257) was a touch under Skyscanner, but it's a reseller (you book and pay Kiwi, not the airline), and its full-service and business fares came in well above everyone else, Garuda at S$391 and S$807, so we rank it last. Prices are live and drift by the hour, so read the pattern, not the exact figure.
Every fare under about S$270 on this route is a budget ticket with only a cabin bag. Scoot, Jetstar and TransNusa charge for a checked bag, a chosen seat and food separately, and it adds up fast: a checked bag alone is S$30 to S$50 each way.
So the honest comparison isn't S$187 versus S$289. It's S$187 plus your bag against a full-service Garuda fare that already includes one. Add the bag on every tool before you decide, or the cheap headline will talk you into the worse deal.