diff --git a/web/components/probability-selector.tsx b/web/components/probability-selector.tsx
index 2fc03787..74dab3c6 100644
--- a/web/components/probability-selector.tsx
+++ b/web/components/probability-selector.tsx
@@ -4,8 +4,11 @@ export function ProbabilitySelector(props: {
   probabilityInt: number
   setProbabilityInt: (p: number) => void
   isSubmitting?: boolean
+  minProb?: number
+  maxProb?: number
 }) {
-  const { probabilityInt, setProbabilityInt, isSubmitting } = props
+  const { probabilityInt, setProbabilityInt, isSubmitting, minProb, maxProb } =
+    props
 
   return (
     <Row className="items-center gap-2">
@@ -15,19 +18,28 @@ export function ProbabilitySelector(props: {
           value={probabilityInt}
           className="input input-bordered input-md text-lg"
           disabled={isSubmitting}
-          min={1}
-          max={99}
+          min={minProb ?? 1}
+          max={maxProb ?? 99}
           onChange={(e) =>
             setProbabilityInt(parseInt(e.target.value.substring(0, 2)))
           }
+          onBlur={() =>
+            setProbabilityInt(
+              maxProb && probabilityInt > maxProb
+                ? maxProb
+                : minProb && probabilityInt < minProb
+                ? minProb
+                : probabilityInt
+            )
+          }
         />
         <span>%</span>
       </label>
       <input
         type="range"
         className="range range-primary"
-        min={1}
-        max={99}
+        min={minProb ?? 1}
+        max={maxProb ?? 99}
         value={probabilityInt}
         onChange={(e) => setProbabilityInt(parseInt(e.target.value))}
       />
diff --git a/web/pages/create.tsx b/web/pages/create.tsx
index b668fffb..4a4a07b5 100644
--- a/web/pages/create.tsx
+++ b/web/pages/create.tsx
@@ -106,11 +106,14 @@ export function NewContract(props: { question: string; tag?: string }) {
 
     setIsSubmitting(true)
 
+    const boundedProb =
+      initialProb > 90 ? 90 : initialProb < 10 ? 10 : initialProb
+
     const result: any = await createContract({
       question,
       outcomeType,
       description,
-      initialProb,
+      initialProb: boundedProb,
       ante,
       closeTime,
       tags,
@@ -172,6 +175,8 @@ export function NewContract(props: { question: string; tag?: string }) {
           <ProbabilitySelector
             probabilityInt={initialProb}
             setProbabilityInt={setInitialProb}
+            minProb={10}
+            maxProb={90}
           />
         </div>
       )}