diff --git a/src/app.js b/src/app.js
index adfc825cab..2ce9980ffd 100644
--- a/src/app.js
+++ b/src/app.js
@@ -475,7 +475,8 @@ var run = function () {
           callback(null, executionContext.web3().fromWei(balance, 'ether'))
         }
       })
-    }
+    },
+    currentblockGasLimit: () => { return executionContext.currentblockGasLimit() }
   }
   var renderer = new Renderer(rendererAPI, compiler.event)
 
diff --git a/src/app/execution-context.js b/src/app/execution-context.js
index ccba55f739..f14e91924d 100644
--- a/src/app/execution-context.js
+++ b/src/app/execution-context.js
@@ -123,6 +123,23 @@ function ExecutionContext () {
     }
   }
 
+  this.currentblockGasLimit = function () {
+    return this.blockGasLimit
+  }
+
+  this.blockGasLimitDefault = 4300000
+  this.blockGasLimit = this.blockGasLimitDefault
+  setInterval(() => {
+    web3.eth.getBlock('latest', (err, block) => {
+      if (!err) {
+        // we can't use the blockGasLimit cause the next blocks could have a lower limit : https://github.com/ethereum/remix/issues/506
+        this.blockGasLimit = (block && block.gasLimit) ? Math.floor(block.gasLimit - (5 * block.gasLimit) / 1024) : this.blockGasLimitDefault
+      } else {
+        this.blockGasLimit = this.blockGasLimitDefault
+      }
+    })
+  }, 15000)
+
   function setProviderFromEndpoint (endpoint) {
     if (endpoint === 'ipc') {
       web3.setProvider(new web3.providers.IpcProvider())
diff --git a/src/app/renderer.js b/src/app/renderer.js
index c97106950c..db39e6ae5e 100644
--- a/src/app/renderer.js
+++ b/src/app/renderer.js
@@ -111,6 +111,7 @@ Renderer.prototype.error = function (message, container, options) {
 }
 
 Renderer.prototype.contracts = function (data, source) {
+  var self = this
   var retrieveMetadataHash = function (bytecode) {
     var match = /a165627a7a72305820([0-9a-f]{64})0029$/.exec(bytecode)
     if (match) {
@@ -210,7 +211,7 @@ Renderer.prototype.contracts = function (data, source) {
     code += '\n   {' +
       '\n     from: web3.eth.accounts[0], ' +
       "\n     data: '0x" + bytecode + "', " +
-      "\n     gas: '4700000'" +
+      "\n     gas: '" + self.appAPI.currentblockGasLimit() + "'" +
       '\n   }, function (e, contract){' +
       '\n    console.log(e, contract);' +
       "\n    if (typeof contract.address !== 'undefined') {" +
@@ -313,7 +314,6 @@ Renderer.prototype.contracts = function (data, source) {
     return $('<div class="contractDetails"/>').append(button).append(details)
   }
 
-  var self = this
   var renderOutputModifier = function (contractName, $contractOutput) {
     var contract = data.contracts[contractName]
     var ctrSource = self.appAPI.currentCompiledSourceCode()
diff --git a/src/app/txRunner.js b/src/app/txRunner.js
index 5c48b87f91..03b48b708f 100644
--- a/src/app/txRunner.js
+++ b/src/app/txRunner.js
@@ -69,30 +69,23 @@ TxRunner.prototype.execute = function () {
         if (err) {
           return callback(err, gasEstimation)
         }
-        self.web3.eth.getBlock('latest', function (err, block) {
+        var blockGasLimit = self.executionContext.currentblockGasLimit()
+        // NOTE: estimateGas very likely will return a large limit if execution of the code failed
+        //       we want to be able to run the code in order to debug and find the cause for the failure
+        if (gasEstimation > gasLimit) {
+          return callback('Gas required exceeds limit: ' + gasLimit)
+        }
+        if (gasEstimation > blockGasLimit) {
+          return callback('Gas required exceeds block gas limit: ' + gasLimit)
+        }
+        tx.gas = gasEstimation
+        var sendTransaction = self.personalMode ? self.web3.personal.sendTransaction : self.web3.eth.sendTransaction
+        sendTransaction(tx, function (err, resp) {
           if (err) {
-            return callback(err)
-          } else {
-            // NOTE: estimateGas very likely will return a large limit if execution of the code failed
-            //       we want to be able to run the code in order to debug and find the cause for the failure
-            // we can't use the blockGasLimit cause the next blocks could have a lower limit : https://github.com/ethereum/remix/issues/506
-            var blockGasLimit = Math.floor(block.gasLimit - (5 * block.gasLimit) / 1024)
-            if (gasEstimation > gasLimit) {
-              return callback('Gas required exceeds limit: ' + gasLimit)
-            }
-            if (gasEstimation > blockGasLimit) {
-              return callback('Gas required exceeds block gas limit: ' + gasLimit)
-            }
-            tx.gas = gasEstimation
-            var sendTransaction = self.personalMode ? self.web3.personal.sendTransaction : self.web3.eth.sendTransaction
-            sendTransaction(tx, function (err, resp) {
-              if (err) {
-                return callback(err, resp)
-              }
-
-              tryTillResponse(self.web3, resp, callback)
-            })
+            return callback(err, resp)
           }
+
+          tryTillResponse(self.web3, resp, callback)
         })
       })
     }