diff --git a/src/rpc/mining.cpp b/src/rpc/mining.cpp
index caad78859..4fd632dfc 100644
--- a/src/rpc/mining.cpp
+++ b/src/rpc/mining.cpp
@@ -806,13 +806,13 @@ UniValue estimatesmartfee(const JSONRPCRequest& request)
 {
     if (request.fHelp || request.params.size() < 1 || request.params.size() > 2)
         throw std::runtime_error(
-            "estimatesmartfee nblocks (\"estimate_mode\")\n"
+            "estimatesmartfee conf_target (\"estimate_mode\")\n"
             "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
-            "confirmation within nblocks blocks if possible and return the number of blocks\n"
+            "confirmation within conf_target blocks if possible and return the number of blocks\n"
             "for which the estimate is valid. Uses virtual transaction size as defined\n"
             "in BIP 141 (witness data is discounted).\n"
             "\nArguments:\n"
-            "1. nblocks         (numeric) Confirmation target in blocks (1 - 1008)\n"
+            "1. conf_target     (numeric) Confirmation target in blocks (1 - 1008)\n"
             "2. \"estimate_mode\" (string, optional, default=CONSERVATIVE) The fee estimate mode.\n"
             "                   Whether to return a more conservative estimate which also satisfies\n"
             "                   a longer history. A conservative estimate potentially returns a\n"
@@ -839,10 +839,7 @@ UniValue estimatesmartfee(const JSONRPCRequest& request)
 
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VSTR});
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
-    int nBlocks = request.params[0].get_int();
-    if (nBlocks < 1 || (unsigned int)nBlocks > ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE)) {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid nblocks");
-    }
+    unsigned int conf_target = ParseConfirmTarget(request.params[0]);
     bool conservative = true;
     if (request.params.size() > 1 && !request.params[1].isNull()) {
         FeeEstimateMode fee_mode;
@@ -855,7 +852,7 @@ UniValue estimatesmartfee(const JSONRPCRequest& request)
     UniValue result(UniValue::VOBJ);
     UniValue errors(UniValue::VARR);
     FeeCalculation feeCalc;
-    CFeeRate feeRate = ::feeEstimator.estimateSmartFee(nBlocks, &feeCalc, conservative);
+    CFeeRate feeRate = ::feeEstimator.estimateSmartFee(conf_target, &feeCalc, conservative);
     if (feeRate != CFeeRate(0)) {
         result.push_back(Pair("feerate", ValueFromAmount(feeRate.GetFeePerK())));
     } else {
@@ -870,18 +867,18 @@ UniValue estimaterawfee(const JSONRPCRequest& request)
 {
     if (request.fHelp || request.params.size() < 1 || request.params.size() > 2)
         throw std::runtime_error(
-            "estimaterawfee nblocks (threshold)\n"
+            "estimaterawfee conf_target (threshold)\n"
             "\nWARNING: This interface is unstable and may disappear or change!\n"
             "\nWARNING: This is an advanced API call that is tightly coupled to the specific\n"
             "         implementation of fee estimation. The parameters it can be called with\n"
             "         and the results it returns will change if the internal implementation changes.\n"
             "\nEstimates the approximate fee per kilobyte needed for a transaction to begin\n"
-            "confirmation within nblocks blocks if possible. Uses virtual transaction size as defined\n"
-            "in BIP 141 (witness data is discounted).\n"
+            "confirmation within conf_target blocks if possible. Uses virtual transaction size as\n"
+            "defined in BIP 141 (witness data is discounted).\n"
             "\nArguments:\n"
-            "1. nblocks     (numeric) Confirmation target in blocks (1 - 1008)\n"
+            "1. conf_target (numeric) Confirmation target in blocks (1 - 1008)\n"
             "2. threshold   (numeric, optional) The proportion of transactions in a given feerate range that must have been\n"
-            "               confirmed within nblocks in order to consider those feerates as high enough and proceed to check\n"
+            "               confirmed within conf_target in order to consider those feerates as high enough and proceed to check\n"
             "               lower buckets.  Default: 0.95\n"
             "\nResult:\n"
             "{\n"
@@ -911,10 +908,7 @@ UniValue estimaterawfee(const JSONRPCRequest& request)
 
     RPCTypeCheck(request.params, {UniValue::VNUM, UniValue::VNUM}, true);
     RPCTypeCheckArgument(request.params[0], UniValue::VNUM);
-    int nBlocks = request.params[0].get_int();
-    if (nBlocks < 1 || (unsigned int)nBlocks > ::feeEstimator.HighestTargetTracked(FeeEstimateHorizon::LONG_HALFLIFE)) {
-        throw JSONRPCError(RPC_INVALID_PARAMETER, "Invalid nblocks");
-    }
+    unsigned int conf_target = ParseConfirmTarget(request.params[0]);
     double threshold = 0.95;
     if (!request.params[1].isNull()) {
         threshold = request.params[1].get_real();
@@ -930,9 +924,9 @@ UniValue estimaterawfee(const JSONRPCRequest& request)
         EstimationResult buckets;
 
         // Only output results for horizons which track the target
-        if ((unsigned int)nBlocks > ::feeEstimator.HighestTargetTracked(horizon)) continue;
+        if (conf_target > ::feeEstimator.HighestTargetTracked(horizon)) continue;
 
-        feeRate = ::feeEstimator.estimateRawFee(nBlocks, threshold, horizon, &buckets);
+        feeRate = ::feeEstimator.estimateRawFee(conf_target, threshold, horizon, &buckets);
         UniValue horizon_result(UniValue::VOBJ);
         UniValue errors(UniValue::VARR);
         UniValue passbucket(UniValue::VOBJ);
@@ -983,9 +977,9 @@ static const CRPCCommand commands[] =
     { "generating",         "generatetoaddress",      &generatetoaddress,      true,  {"nblocks","address","maxtries"} },
 
     { "util",               "estimatefee",            &estimatefee,            true,  {"nblocks"} },
-    { "util",               "estimatesmartfee",       &estimatesmartfee,       true,  {"nblocks", "estimate_mode"} },
+    { "util",               "estimatesmartfee",       &estimatesmartfee,       true,  {"conf_target", "estimate_mode"} },
 
-    { "hidden",             "estimaterawfee",         &estimaterawfee,         true,  {"nblocks", "threshold"} },
+    { "hidden",             "estimaterawfee",         &estimaterawfee,         true,  {"conf_target", "threshold"} },
 };
 
 void RegisterMiningRPCCommands(CRPCTable &t)