21+Information only. Not betting advice.Problem gambling? 1-800-GAMBLERResponsible gaming

Community-built, affiliate-funded, no upsell

The odds-comparison extension that's free. Because affiliate revenue pays for it.

Runs on 43+ sportsbook sites. Compares 78+ price sources. Doesn't ask for an account. Doesn't upsell you to a paid tier.

Install Free ExtensionFree forever · No account · Open about affiliate revenue
Interactive preview: drag the slider to compare the same odds without OddsGuard (greyed out) versus with OddsGuard's live savings badges on every better price.

Already protecting bettors across every major book

  • +$50,938
    +$
    In better prices on game lines right now
  • 43+
    Sportsbooks supported
  • 78+
    Odds providers compared
  • 129+
    Active leagues right now
  • 1,739+
    Events with live odds
  • +7.3%
    Avg price spread between books
  • +18.0%
    Avg uplift on best market per match
  • +$1,100
    +$
    Biggest extra return on a $100 game-line bet

Where the price-shopping money is, broken down

Pre-match

Where the smart money sets the line

  • Moneylines
    vs avg book
    +6.9%
    LowestBest
    Up to +18.0% between books
  • Spreads
    vs avg book
    +6.3%
    LowestBest
    Up to +13.4% between books
  • Totals
    vs avg book
    +4.8%
    LowestBest
    Up to +10.0% between books

Live · in-play right now

Mispriced quotes that move every second

  • Moneylines
    vs avg book
    +29.8%
    LowestBest
    Up to +74.2% between books
  • Spreads
    vs avg book
    +18.2%
    LowestBest
    Up to +40.1% between books
  • Totals
    vs avg book
    +21.0%
    LowestBest
    Up to +25.3% between books

Compound your edge

What line-shopping every leg means on a $100 stake (or local-currency equivalent)

  • 4-leg parlay

    Between books

    +94.0% payout
    +$

    Extra winnings if every leg hits

    Best book

    $6,437

    Lowest

    $3,318

  • 5-leg parlay

    Between books

    +129.0% payout
    +$

    Extra winnings if every leg hits

    Best book

    $18,232

    Lowest

    $7,963

Illustrative mixed-market parlay (avg leg ~2.40 decimal). Real parlays vary; the compounded edge is independent of the base leg odds.

Futures & outrights — where price gaps explode

  • Average outright edge
    +56.8%
    Average price uplift across every priced outright outcome
    106+Outright outcomes priced right now
  • Total overlay savings
    +$
    Combined price improvement across every priced outright outcome on a $100 stake
    Biggest single price gap+$150,000

The problem

Line shopping without the headache.

  • You open six tabs just to find one line.
  • You miss closing line value while switching apps.
  • You paid for a dashboard you open twice a week.
  • You can't tell whether the line you took was actually good.

Why it matters

We get asked "what's the catch" on every thread. There isn't one. We make money when a user signs up with a book through our link. Same model as every travel or shopping comparison site you already use.

The solution

The transparency layer for the books you already use.

OddsGuard runs quietly inside the sportsbook sites you visit and shows the best available price for every line, so you never have to switch tabs to check.

  • Compares 78+ price sources in under a second.
  • Overlays 43+ sportsbook sites. No extra tabs.
  • Flags stale lines and better prices before you commit.
  • Runs locally. No betting data collected. No account required.

How OddsGuard pays for itself

Two badges. Real money saved on every bet.

Like Honey at checkout, but for your lines. Two on-page badges do the heavy lifting so you stop overpaying and stop missing +EV plays. Every bet, every page, every sportsbook we cover.

Hidden dollars: Save on every bet

We shop the lines so you don't have to.

Five tiers, Minimal to Fire. Whichever sportsbook has the better line, you see exactly how much you would save before you click bet.

Savings at a glance

Five colour-coded tiers from Minimal to Fire.
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+EV: Bet sharper

We do the math so you get the edge.

We compare every line to the de-vigged consensus across 43+ books. If a bet is priced better than fair value, you get a +EV badge. No spreadsheets, no math.

Expected Value badges

+EV? We label it. No math required.
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Live demo

See it working on real odds.

This is the extension running on live data. Switch books, change sports, and watch the best price update in real time.

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How it works

Install once. Better lines, forever.

  1. Install the extension

    Chrome, Edge, Firefox, or Safari. We'll detect your browser and ship the right one.

  2. Open your sportsbook

    OddsGuard activates on the 43+ supported sites. Everywhere else it stays out of your way.

  3. See the better price

    Our overlay shows the best available line from the market, inline, on every bet.

Life after install

What changes the first week you install.

No account, no tracking

Runs locally. We don't see your balance, your bets, or your account data. Delete the extension and nothing of yours is left anywhere.

Free forever

Supported by affiliate partnerships, same as every travel or shopping comparison site. You pay the same whichever book you pick.

Community-informed

We're adding new book adapters based on community requests. Post what you use; if we're not on it, we'll fix that.

Works where you bet

Works where you already bet.

43+ sportsbook sites supported. 78+ price-comparison sources feeding the market.

What Bettors Are Saying

Join 1,000s of Smarter Bettors

14 5-star reviews from bettors using OddsGuard today.

Common questions

Answers to the stuff that usually stops you.

What's the catch? How are you really making money?
Affiliate commissions. When a user clicks through to a sportsbook and signs up, the book pays us a referral fee. Same as travel sites, credit-card comparison sites, Honey, etc. Your price doesn't change. We earn the same whichever book you pick.
Is this going to become a paid product later?
The comparison product is free forever. We've considered adding optional premium features (advanced alerts, custom filters) down the road, but the "see the best line" core stays free. If/when a paid tier launches, it'll be opt-in and the free tier won't get worse.
Do you sell or share my data?
No. The extension runs locally on your device and reads the public odds on the page you're looking at. We don't have an account system for the extension, so there's no user database to sell.
Will it slow down my browser?
The extension only loads on supported sportsbook sites. Everywhere else it does nothing. No background polling on random pages.
Do you see my bets or my account data?
No. OddsGuard runs locally on your device, reads the public odds on the page, and compares them to the market. It does not read account balances, bet history, or personal data.
Which sportsbooks does it work on?
Most major US and international books. See the full supported list at our home page bookmaker section. The list updates as we add new adapters.

More in our full FAQ.

Install OddsGuard.

78+ books compared in real time. 43+ sportsbook sites overlaid. One extension.

InstallFree forever · No account · Open about affiliate revenue

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