diff --git a/backend/windmill-api/src/flows.rs b/backend/windmill-api/src/flows.rs
index d2c93adc9209c..fc4fd9c1db5ae 100644
--- a/backend/windmill-api/src/flows.rs
+++ b/backend/windmill-api/src/flows.rs
@@ -85,6 +85,38 @@ pub fn global_service() -> Router {
         .route("/hub/get/:id", get(get_hub_flow_by_id))
 }
 
+fn validate_flow_value(flow_value: &serde_json::Value) -> Result<()> {
+    #[cfg(not(feature = "enterprise"))]
+    if flow_value
+        .get("ws_error_handler_muted")
+        .map(|val| val.as_bool().unwrap_or(false))
+        .is_some_and(|val| val)
+    {
+        return Err(Error::BadRequest(
+            "Muting the error handler for certain flow is only available in enterprise version"
+                .to_string(),
+        ));
+    }
+
+    if let Some(modules) = flow_value.get("modules").and_then(|m| m.as_array()) {
+        for module in modules {
+            if let Some(retry) = module.get("retry") {
+                if let Some(exponential) = retry.get("exponential") {
+                    let seconds = exponential.get("seconds").and_then(|s| s.as_u64()).ok_or(
+                        Error::BadRequest("Exponential backoff base (seconds) must be a valid positive integer".to_string()),
+                    )?;
+                    if seconds == 0 {
+                        return Err(Error::BadRequest(
+                                "Exponential backoff base (seconds) must be greater than 0. A base of 0 would cause immediate retries.".to_string(),
+                            ));
+                    }
+                }
+            }
+        }
+    }
+    Ok(())
+}
+
 #[derive(Serialize, FromRow)]
 pub struct SearchFlow {
     path: String,
@@ -411,18 +443,8 @@ async fn create_flow(
             ));
         }
     }
-    #[cfg(not(feature = "enterprise"))]
-    if nf
-        .value
-        .get("ws_error_handler_muted")
-        .map(|val| val.as_bool().unwrap_or(false))
-        .is_some_and(|val| val)
-    {
-        return Err(Error::BadRequest(
-            "Muting the error handler for certain flow is only available in enterprise version"
-                .to_string(),
-        ));
-    }
+
+    validate_flow_value(&nf.value)?;
 
     // cron::Schedule::from_str(&ns.schedule).map_err(|e| error::Error::BadRequest(e.to_string()))?;
     let authed = maybe_refresh_folders(&nf.path, &w_id, authed, &db).await;
@@ -744,18 +766,7 @@ async fn update_flow(
     let flow_path = flow_path.to_path();
     check_scopes(&authed, || format!("flows:write:{}", flow_path))?;
 
-    #[cfg(not(feature = "enterprise"))]
-    if nf
-        .value
-        .get("ws_error_handler_muted")
-        .map(|val| val.as_bool().unwrap_or(false))
-        .is_some_and(|val| val)
-    {
-        return Err(Error::BadRequest(
-            "Muting the error handler for certain flow is only available in enterprise version"
-                .to_string(),
-        ));
-    }
+    validate_flow_value(&nf.value)?;
 
     let authed = maybe_refresh_folders(&flow_path, &w_id, authed, &db).await;
     let mut tx = user_db.clone().begin(&authed).await?;
diff --git a/frontend/src/lib/components/FlowBuilder.svelte b/frontend/src/lib/components/FlowBuilder.svelte
index 22e22f2b7a5f4..598474521ee8c 100644
--- a/frontend/src/lib/components/FlowBuilder.svelte
+++ b/frontend/src/lib/components/FlowBuilder.svelte
@@ -80,6 +80,7 @@
 	import { StepsInputArgs } from './flows/stepsInputArgs.svelte'
 	import { aiChatManager } from './copilot/chat/AIChatManager.svelte'
 	import type { GraphModuleState } from './graph'
+	import { validateRetryConfig } from '$lib/utils'
 	import {
 		setStepHistoryLoaderContext,
 		StepHistoryLoader,
@@ -427,6 +428,15 @@
 		loadingSave = true
 		try {
 			const flow = cleanInputs(flowStore.val)
+			
+			if (flow.value?.modules) {
+				for (const module of flow.value.modules) {
+					const error = validateRetryConfig(module.retry)
+					if (error) {
+						throw new Error(error)
+					}
+				}
+			}
 			// console.log('flow', computeUnlockedSteps(flow)) // del
 			// loadingSave = false // del
 			// return
diff --git a/frontend/src/lib/components/flows/content/FlowRetries.svelte b/frontend/src/lib/components/flows/content/FlowRetries.svelte
index 8d14890961317..94c5822334c9b 100644
--- a/frontend/src/lib/components/flows/content/FlowRetries.svelte
+++ b/frontend/src/lib/components/flows/content/FlowRetries.svelte
@@ -14,6 +14,7 @@
 	import type { FlowEditorContext } from '../types'
 	import { getStepPropPicker } from '../previousResults'
 	import { NEVER_TESTED_THIS_FAR } from '../models'
+	import { validateRetryConfig } from '$lib/utils'
 
 	interface Props {
 		flowModuleRetry: Retry | undefined
@@ -59,6 +60,10 @@
 			: NEVER_TESTED_THIS_FAR
 	)
 
+	let validationError = $derived.by(() => {
+		return validateRetryConfig(flowModuleRetry)
+	})
+
 	function setConstantRetries() {
 		flowModuleRetry = {
 			...flowModuleRetry,
@@ -247,7 +252,20 @@
 					<span class="text-xs text-tertiary">delay = multiplier * base ^ (number of attempt)</span>
 					<input bind:value={flowModuleRetry.exponential.multiplier} type="number" />
 					<div class="text-xs font-bold !mt-2">Base (in seconds)</div>
-					<input bind:value={flowModuleRetry.exponential.seconds} type="number" step="1" />
+					<input
+						bind:value={flowModuleRetry.exponential.seconds}
+						type="number"
+						step="1"
+						min="1"
+						class={validationError ? 'border-red-500' : ''}
+					/>
+					{#if validationError}
+						<span class="text-xs text-red-500">{validationError}</span>
+					{:else}
+						<span class="text-xs text-tertiary"
+							>Must be ≥ 1. A base of 0 would cause immediate retries.</span
+						>
+					{/if}
 					<div class="text-xs font-bold !mt-2">Randomization factor (percentage)</div>
 					<div class="flex w-full gap-4">
 						{#if !$enterpriseLicense}
diff --git a/frontend/src/lib/utils.ts b/frontend/src/lib/utils.ts
index f37549a127e4f..6b9719daacf35 100644
--- a/frontend/src/lib/utils.ts
+++ b/frontend/src/lib/utils.ts
@@ -10,7 +10,7 @@ import { deepEqual } from 'fast-equals'
 import YAML from 'yaml'
 import { type UserExt } from './stores'
 import { sendUserToast } from './toast'
-import type { Job, RunnableKind, Script, ScriptLang } from './gen'
+import type { Job, RunnableKind, Script, ScriptLang, Retry } from './gen'
 import type { EnumType, SchemaProperty } from './common'
 import type { Schema } from './common'
 export { sendUserToast }
@@ -1624,3 +1624,13 @@ export function createCache<Keys extends Record<string, any>, T, InitialKeys ext
 export async function wait(ms: number) {
 	return new Promise((resolve) => setTimeout(() => resolve(undefined), ms))
 }
+
+export function validateRetryConfig(retry: Retry | undefined): string | null {
+	if (retry?.exponential?.seconds !== undefined) {
+		const seconds = retry.exponential.seconds
+		if (typeof seconds !== 'number' || !Number.isInteger(seconds) || seconds < 1) {
+			return 'Exponential backoff base (seconds) must be a valid positive integer ≥ 1'
+		}
+	}
+	return null
+}
diff --git a/openflow.openapi.yaml b/openflow.openapi.yaml
index 7aee72475f024..ec7d2291b247f 100644
--- a/openflow.openapi.yaml
+++ b/openflow.openapi.yaml
@@ -87,6 +87,7 @@ components:
               type: integer
             seconds:
               type: integer
+              minimum: 1
             random_factor:
               type: integer
               minimum: 0