- What it does: puts the same bet at several sportsbooks and flags the highest odds.
- What you gain: in real data, the best odds paid on average 4.4% to 6.7% more than the market average.
- What it does not do: it does not tell you whether the bet has value; for that you compare against your own probability.
Bookmark this article: it is a five-step guide and you will want to come back and tick the steps off while you build your own comparison sheet.
Your progress is saved in this browser.
What is an odds comparison tool and what is it for?
A comparison tool puts one bet at several sportsbooks.
It shows you each price, from highest to lowest.
That way you see at a glance where they pay the most for the same thing.
It is the simplest tool for betting better without changing your pick.
It does not tell you what to bet.
It only helps you collect the most you can on the bet you have already decided.
The practice of looking for the best odds has its own name.
It is called line shopping and has its own article with the calculation of the impact on returns.
Here we look at how to use the comparison tool, step by step.
How to use an odds comparison tool in 5 steps
This step-by-step does not promise results.
Better odds improve your expected payout, but they do not change the probability that the outcome happens.
Bet only if you are 18 or older and with money you can afford to lose.
Which number to look at: odds, implied probability and margin
A comparison tool shows three useful things, even if they are sometimes hidden.
The decimal odds are what you collect for each unit staked.
The implied probability is 1 divided by the odds.
The margin is what the sportsbook charges for offering the market.
The margin shows up when you add the implied probabilities of all outcomes.
If they add up to more than 100%, the excess is the sportsbook's margin.
We explain it in the article on the sportsbook margin.
In our data, the 1X2 margin using the market average was 6.1%.
Building the 1X2 with only the best odds for each outcome, it dropped to 1.5%.
That number is a theoretical ceiling: nobody usually gets all three highest odds at the same sportsbook.
How much do odds change from one sportsbook to another? Real data
We calculated the gap across 34,345 football matches.
We compared the best posted odds for each outcome against the market average and against one big sportsbook.
| Outcome | Best vs average | Best vs one big sportsbook |
|---|---|---|
| Home win | +4.4% | +4.8% |
| Draw | +5.4% | +5.6% |
| Away win | +6.7% | +6.4% |
Source: football-data.co.uk, seasons 2019/20, 2021/22 to 2025/26 and the 2026/27 games played so far.
Sample: 34,345 matches from 16 European leagues with complete opening odds.
Leagues: first and second divisions of England, Spain, Italy, Germany and France, plus the Netherlands, Portugal, Belgium, Greece, Scotland and Turkey.
Our own calculation.
The gap is larger on the less likely outcomes.
That makes sense: that is where prices drift further apart between sportsbooks.
And the big reference sportsbook had the best odds in only 10.3% of cases.
Example: 1.90 against 2.00 on the same bet
Let's see what a seemingly small difference means.
All the numbers in this table are an example, not a real result.
Suppose you estimate a probability of 52% for an outcome.
| Data (example) | Odds 1.90 | Odds 2.00 |
|---|---|---|
| Implied probability | 52.6% | 50.0% |
| Expected value per unit | −1.2% | +4.0% |
| 100 bets of 10 units | −12 units | +40 units |
| Difference | 52 units per 1,000 staked |
At 1.90 the bet loses value.
At 2.00 it gains value.
The 0.10 difference in the odds flipped the sign of the expected result.
The actual result of each bet is still uncertain in both cases.
You can repeat the calculation with your own numbers in the expected value calculator.
What else to compare besides the odds
Price is not the only thing that counts.
Before going to the sportsbook with the highest odds, check these points.
- Bet limits: high odds with a low cap may not be useful to you.
- Market rules: what happens if the match is suspended or goes to extra time.
- Withdrawals: timing and conditions for cashing out.
- Bonuses with conditions: see the fine print on bonuses and the rollover.
- License and country: make sure the sportsbook operates legally where you live.
Odds that are 2% better do not make up for a sportsbook that delays payouts.
Safety first, price second.
How to build your own comparison sheet
You do not need a paid tool.
A simple spreadsheet is enough to start.
These are the minimum columns.
- Match, date and exact market.
- Odds at each sportsbook where you have an account.
- Maximum odds (the MAX formula for the row).
- Implied probability of the maximum (1 divided by the odds).
- Your estimated probability and the expected value.
- Sportsbook chosen and final result.
With 20 bets logged you can already see at which sportsbooks it pays to bet more often.
With 100 you see your real pattern.
To sort markets and methods, see the best markets with AI.
Prompt for the AI to build the sheet
You can ask an AI to create the spreadsheet and explain the formulas.
Copy this prompt and change what is in brackets.
Act as an odds analyst. Build me a spreadsheet to compare odds for [MARKET, e.g. football 1X2] across [NUMBER] sportsbooks. Columns: match, date, odds per sportsbook, maximum odds, implied probability of the maximum, my estimated probability, expected value. Give me the exact formulas for Excel or Google Sheets. Add a column with the 1X2 margin: the sum of 1/odds for the three outcomes minus 1. Use only data I give you. If a piece of data is missing, ask me for it and do not invent it.
Then paste in your real odds and ask it to flag the rows with positive expected value.
Always check the math with your own calculator.
Common mistakes when comparing odds
- Comparing markets that look alike but have different rules.
- Choosing the highest odds without looking at the probability.
- Switching sportsbooks for a minimal difference and losing time or balance on transfers.
- Forgetting that the comparison tool shows prices, not results.
- Betting more than planned just because you found a good price.
What to read next
If you want to see the impact on returns of always betting at the best price, continue with line shopping: the silent edge.
If you bet on halves, read the first-half bets guide.
And for goals markets, see team goals.
For the full picture, the parent guide is AI for betting: the complete guide.
And to see how we record each pick, there is the public record and the Betting Journal.
If you want an AI with your own rules, try create your own AI and the AI comparison.
Responsible gambling: betting is only for adults 18 and over.
Never bet money you need to live on.
Frequently asked questions
What is an odds comparison tool?
It is a tool that shows, for the same market, the odds each sportsbook offers.
It saves you from opening several pages one by one.
What is useful is seeing at a glance which one pays the most.
How much do odds change between sportsbooks?
On average, the best odds beat the market average by 4.4% (home), 5.4% (draw) and 6.7% (away).
This is our own calculation over 34,345 matches from 2019/20, 2021/22 to 2025/26 and the 2026/27 games played so far.
In a specific match the gap can be larger or smaller.
Do higher odds mean there is value?
No.
Higher odds are just a better price for the same outcome.
Value appears when your estimated probability is higher than the one implied by those odds.
Calculate it with the expected value calculator.
Do I need accounts at many sportsbooks to use an odds comparison tool?
To take advantage of the best price, yes, you need to be able to bet at the sportsbook that offers it.
Without accounts, the tool still helps you tell whether the price you are being offered is good.
Do not open accounts just for a small difference.
Can I compare odds with a spreadsheet?
Yes.
Write down the match, the market and the odds from each sportsbook you use.
With a formula, you flag the highest one.
At the end of the article there is a prompt for an AI to build the sheet for you.
Does odds comparison work for every sport?
It works for any market with a posted price.
The data in this article comes from football, so the figures apply to football 1X2 markets.
For other sports the gap may be different.