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Sports · Line check

Bring your own line.

Type the American odds your sportsbook shows for every outcome. See the vig you pay, the fair price without it, and what the same outcome costs on Onsides, fee included.

Your sportsbook’s line

Stays in your browser

Same outcome on Onsides (optional)

Side A

Side B

American odds as your sportsbook shows them, for every outcome: −150, +130. We don’t fetch, store or show anyone else’s prices.

What that line costs you

Vig you pay3.48%The implied chances add up to 103.5%, not 100%. The extra is the house margin built into the line.

Outcome	Your line	Implied	Fair (mult.)	Fair (power)
Side A	−150	60.0%	58.0%	58.4%
Side B	+130	43.5%	42.0%	41.6%

Fair (mult.) scales every implied chance down by the same factor. Fair (power) takes more of the margin off long shots, where books usually put it. Neither is a promise; both are estimates of the line without the vig.

Sports · Line check

Bring your own line.

Type the American odds your sportsbook shows for every outcome. See the vig you pay, the fair price without it, and what the same outcome costs on Onsides, fee included.

Your sportsbook’s line

Stays in your browser

Same outcome on Onsides (optional)

Side A

Side B

American odds as your sportsbook shows them, for every outcome: −150, +130. We don’t fetch, store or show anyone else’s prices.

What that line costs you

Vig you pay3.48%The implied chances add up to 103.5%, not 100%. The extra is the house margin built into the line.

Outcome	Your line	Implied	Fair (mult.)	Fair (power)
Side A	−150	60.0%	58.0%	58.4%
Side B	+130	43.5%	42.0%	41.6%