Comparison

Size Guesser vs Fermi

Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.

Head to head
About

Size Guesser

Test your perception of scale by resizing objects to match their real-world dimensions. Compete with friends or play solo across diverse themed categories. Earn points and unlock achievements as you master the art of size comparison.

Highlights
  • 12 themed categories
  • Over 1,000 objects
  • Online 1v1 multiplayer
  • Party Mode for up to 8 players
  • Achievements and stats
  • 27 language support
  • Dark mode
Features
Read full description

Can you guess how big things really are? Size Guesser challenges your sense of scale. One object is drawn to its true size — resize the other until it matches. How accurate can you be? THEMES • Animals — from ants to elephants • Vehicles — cars, planes & more • Buildings — towers & landmarks • Space — stars & planets • Dinosaurs — prehistoric beasts • Sea Life — ocean creatures • Actors — Hollywood stars • Singers — music artists • Sports Gear — balls, bats & more • Athletes — sports legends • World Leaders — heads of state • Maps — countries by area HOW TO PLAY One object is shown at its real size. Drag to resize the other until it matches, then lock in your answer. The closer you get, the more points you score. Finish every round before the clock runs out to clear the level. FEATURES • 12 themed categories with over 1,000 objects • Play online 1v1 with friends or random opponents • Party Mode for 2–8 players on one phone • Achievements and detailed stats • Available in 27 languages • Metric & imperial units • Game Center leaderboards • Dark mode support • Ad-free Premium tier Privacy Policy: https://raw.githubusercontent.com/ekasall/Privacy-Policy-SizeGuesser/refs/heads/main/privacy-policy.md

About

Fermi

Features
Read full description

Seven questions a day, one guess each. No googling: just back-of-the-envelope maths, good assumptions and a bit of intuition. Fermi is a daily estimation game. We ask questions you can't know by heart but can reason your way to: how many people in Turkey are named Mehmet? How many ships passed through the Bosphorus in 2025? How many simits laid end to end would reach the Moon? The game is in Turkish, with questions about Turkey and the world. HOW TO PLAY • Seven new questions every morning at 10:00 (Turkey time): everyday life, places and history, science and numbers. • Type your guess and lock it in. One guess per question. • See the answer right away, scored out of 100: spot on is 100, double or half is 85, ten times off is 50. • Guessing too high or too low counts the same. Your daily score is the average. EVERY ANSWER HAS A STORY • Napkin maths shows how you could have estimated it, step by step. • Every answer comes from official statistics or a reliable source, linked under the question. • See where your guess landed among everyone else's. COMPARE, SHARE, COLLECT • Pick a nickname and climb the daily leaderboard. • Share your result as a card or an emoji grid. • Keep your streak alive and collect 11 badges. • Your profile shows the last 14 days, your strongest topics and how close your answers were. RECORD YOURSELF • Record yourself while you guess: your face on top, the question and your score below, ready for Reels, TikTok and Shorts. • Your face is centred automatically; drag and zoom to adjust it. Voice-only works too. Built-in calculator and scratchpad, archive of past days, optional daily reminder, dark mode and VoiceOver. PLAY WITH FRIENDS • Add friends by username, invite link or QR code. • Duels: 5 questions, 40 seconds each, the same questions for both of you. Win to raise your duel rating. • Open duels: challenge anyone, or join someone else's. • Groups: compare daily, weekly and monthly scores with family, class or colleagues. • Topic practice: 5-question rounds in 10 topics. FERMI PRO (OPTIONAL SUBSCRIPTION) The daily puzzle is free for everyone. Pro adds unlimited duels and practice, groups of up to 100 with history, and detailed stats. • Fermi Pro Aylık (monthly): 1-month auto-renewable subscription. • Fermi Pro Yıllık (yearly): 1-year auto-renewable subscription; new subscribers get a 7-day free trial. Prices are shown in the app before you buy. Payment is charged to your Apple ID when you confirm the purchase. The subscription renews automatically for the same length and price unless cancelled at least 24 hours before the end of the current period; manage or cancel it in Settings → Apple ID → Subscriptions. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Privacy Policy: https://fermi.tr/gizlilik PRIVACY No tracking, and we never sell your data. Some days' puzzles have a sponsor, shown as a single line under the puzzle number. The daily puzzle needs no account; friends features use Sign in with Apple or e-mail. Profile photos are reviewed before they appear, and you can block or report any player.

Screenshots

Size Guesser4 screens
Fermi4 screens

Verdict

The call

The clearest difference is ads: Fermi at none against Size Guesser's shown. On price, update cadence, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Size Guesser sells 1 one-off in-app purchase and Fermi sells 2 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

UpkeepUpdate frequency

Size Guesser ships an update weekly, Fermi every 4 days. The most recent releases landed on November 3, 2026 and October 29, 2026 respectively.

Scorecard1 real difference · 9 level
Size Guesser versus Fermi: the parameters behind the verdict, then further details
ParameterSize GuesserFermi
PriceFreeFree
Rating4.5 (2 ratings) — better—
Positive reviews100.0% of reviews—
Number of ratings2 — better—
Update frequencyWeeklyEvery 4 days — better
AdsYesNo — better
In-app purchasesYesYes
MonetizationFree with in-app purchases—
DevicesiPhoneiPhone, iPad — better
Requires iOS18.618.0 — better
Further details — not scored
Size108 MB13 MB
Age rating4+4+
DeveloperEMIRHAN KASALAppFusion Labs

In-app purchases

1 purchases

Size Guesser

One-time1
  • Premium Upgrade$2.99
2 purchases

Fermi

Subscriptions2
  • Fermi Pro · aylık$0.991 Month
  • Fermi Pro · yıllık7 Days trial$7.991 Year

Questions

Is Size Guesser free?
Size Guesser is free to download, with in-app purchases available.
Is Fermi free?
Fermi is free to download, with in-app purchases available.
Do Size Guesser or Fermi have ads?
Size Guesser shows ads; Fermi does not.
Which is updated more often, Size Guesser or Fermi?
Size Guesser ships an update weekly, and Fermi every 4 days. Most recently, Size Guesser was updated on November 3, 2026 and Fermi on October 29, 2026.

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