diff --git a/js/src/abi/util/pad.js b/js/src/abi/util/pad.js
index a7d940431..5a6751a4f 100644
--- a/js/src/abi/util/pad.js
+++ b/js/src/abi/util/pad.js
@@ -46,7 +46,8 @@ function stringToBytes (input) {
   if (isArray(input)) {
     return input;
   } else if (input.substr(0, 2) === '0x') {
-    return input.substr(2).toLowerCase().match(/.{1,2}/g).map((value) => parseInt(value, 16));
+    const matches = input.substr(2).toLowerCase().match(/.{1,2}/g) || [];
+    return matches.map((value) => parseInt(value, 16));
   } else {
     return input.split('').map((char) => char.charCodeAt(0));
   }
diff --git a/js/src/modals/DeployContract/DetailsStep/detailsStep.js b/js/src/modals/DeployContract/DetailsStep/detailsStep.js
index 854715396..6e23f79c9 100644
--- a/js/src/modals/DeployContract/DetailsStep/detailsStep.js
+++ b/js/src/modals/DeployContract/DetailsStep/detailsStep.js
@@ -15,10 +15,10 @@
 // along with Parity.  If not, see <http://www.gnu.org/licenses/>.
 
 import React, { Component, PropTypes } from 'react';
-import { MenuItem } from 'material-ui';
 
-import { AddressSelect, Form, Input, InputAddressSelect, Select } from '../../../ui';
+import { AddressSelect, Form, Input, TypedInput } from '../../../ui';
 import { validateAbi } from '../../../util/validation';
+import { parseAbiType } from '../../../util/abi';
 
 import styles from '../deployContract.css';
 
@@ -103,6 +103,7 @@ export default class DetailsStep extends Component {
           value={ code }
           onSubmit={ this.onCodeChange }
           readOnly={ readOnly } />
+
         { this.renderConstructorInputs() }
       </Form>
     );
@@ -117,59 +118,23 @@ export default class DetailsStep extends Component {
     }
 
     return inputs.map((input, index) => {
-      const onChange = (event, value) => this.onParamChange(index, value);
-      const onChangeBool = (event, _index, value) => this.onParamChange(index, value === 'true');
-      const onSubmit = (value) => this.onParamChange(index, value);
-      const label = `${input.name}: ${input.type}`;
-      let inputBox = null;
+      const onChange = (value) => this.onParamChange(index, value);
 
-      switch (input.type) {
-        case 'address':
-          inputBox = (
-            <InputAddressSelect
-              accounts={ accounts }
-              editing
-              label={ label }
-              value={ params[index] }
-              error={ paramsError[index] }
-              onChange={ onChange } />
-          );
-          break;
-
-        case 'bool':
-          const boolitems = ['false', 'true'].map((bool) => {
-            return (
-              <MenuItem
-                key={ bool }
-                value={ bool }
-                label={ bool }>{ bool }</MenuItem>
-            );
-          });
-          inputBox = (
-            <Select
-              label={ label }
-              value={ params[index] ? 'true' : 'false' }
-              error={ paramsError[index] }
-              onChange={ onChangeBool }>
-              { boolitems }
-            </Select>
-          );
-          break;
-
-        default:
-          inputBox = (
-            <Input
-              label={ label }
-              value={ params[index] }
-              error={ paramsError[index] }
-              onSubmit={ onSubmit } />
-            );
-          break;
-      }
+      const label = `${input.name ? `${input.name}: ` : ''}${input.type}`;
+      const value = params[index];
+      const error = paramsError[index];
+      const param = parseAbiType(input.type);
 
       return (
         <div key={ index } className={ styles.funcparams }>
-          { inputBox }
+          <TypedInput
+            label={ label }
+            value={ value }
+            error={ error }
+            accounts={ accounts }
+            onChange={ onChange }
+            param={ param }
+          />
         </div>
       );
     });
@@ -200,35 +165,14 @@ export default class DetailsStep extends Component {
     const { abiError, abiParsed } = validateAbi(abi, api);
 
     if (!abiError) {
-      const { inputs } = abiParsed.find((method) => method.type === 'constructor') || { inputs: [] };
+      const { inputs } = abiParsed
+        .find((method) => method.type === 'constructor') || { inputs: [] };
+
       const params = [];
 
       inputs.forEach((input) => {
-        switch (input.type) {
-          case 'address':
-            params.push('0x');
-            break;
-
-          case 'bool':
-            params.push(false);
-            break;
-
-          case 'bytes':
-            params.push('0x');
-            break;
-
-          case 'uint':
-            params.push('0');
-            break;
-
-          case 'string':
-            params.push('');
-            break;
-
-          default:
-            params.push('0');
-            break;
-        }
+        const param = parseAbiType(input.type);
+        params.push(param.default);
       });
 
       onParamsChange(params);
diff --git a/js/src/modals/DeployContract/deployContract.js b/js/src/modals/DeployContract/deployContract.js
index 768723d1f..a99b49412 100644
--- a/js/src/modals/DeployContract/deployContract.js
+++ b/js/src/modals/DeployContract/deployContract.js
@@ -101,7 +101,8 @@ export default class DeployContract extends Component {
         steps={ deployError ? null : steps }
         title={ deployError ? 'deployment failed' : null }
         waiting={ [1] }
-        visible>
+        visible
+        scroll>
         { this.renderStep() }
       </Modal>
     );
@@ -118,8 +119,22 @@ export default class DeployContract extends Component {
         onClick={ this.onClose } />
     );
 
+    const closeBtn = (
+      <Button
+        icon={ <ContentClear /> }
+        label='Close'
+        onClick={ this.onClose } />
+    );
+
+    const closeBtnOk = (
+      <Button
+        icon={ <ActionDoneAll /> }
+        label='Close'
+        onClick={ this.onClose } />
+    );
+
     if (deployError) {
-      return cancelBtn;
+      return closeBtn;
     }
 
     switch (step) {
@@ -134,17 +149,10 @@ export default class DeployContract extends Component {
         ];
 
       case 1:
-        return [
-          cancelBtn
-        ];
+        return [ closeBtn ];
 
       case 2:
-        return [
-          <Button
-            icon={ <ActionDoneAll /> }
-            label='Close'
-            onClick={ this.onClose } />
-        ];
+        return [ closeBtnOk ];
     }
   }
 
@@ -277,8 +285,6 @@ export default class DeployContract extends Component {
       return;
     }
 
-    console.log('onDeploymentState', data);
-
     switch (data.state) {
       case 'estimateGas':
       case 'postTransaction':
diff --git a/js/src/ui/Form/AddressSelect/addressSelect.css b/js/src/ui/Form/AddressSelect/addressSelect.css
index 98dab4355..30671db73 100644
--- a/js/src/ui/Form/AddressSelect/addressSelect.css
+++ b/js/src/ui/Form/AddressSelect/addressSelect.css
@@ -39,6 +39,10 @@
   position: absolute;
   left: 0;
   top: 35px;
+
+  &.noLabel {
+    top: 11px;
+  }
 }
 
 .paddedInput input {
diff --git a/js/src/ui/Form/AddressSelect/addressSelect.js b/js/src/ui/Form/AddressSelect/addressSelect.js
index ac7f2da51..97195efe7 100644
--- a/js/src/ui/Form/AddressSelect/addressSelect.js
+++ b/js/src/ui/Form/AddressSelect/addressSelect.js
@@ -106,15 +106,21 @@ export default class AddressSelect extends Component {
   }
 
   renderIdentityIcon (inputValue) {
-    const { error, value } = this.props;
+    const { error, value, label } = this.props;
 
     if (error || !inputValue || value.length !== 42) {
       return null;
     }
 
+    const classes = [ styles.icon ];
+
+    if (!label) {
+      classes.push(styles.noLabel);
+    }
+
     return (
       <IdentityIcon
-        className={ styles.icon }
+        className={ classes.join(' ') }
         inline center
         address={ value } />
     );
diff --git a/js/src/ui/Form/Input/input.js b/js/src/ui/Form/Input/input.js
index 27c270834..e99b4ae6b 100644
--- a/js/src/ui/Form/Input/input.js
+++ b/js/src/ui/Form/Input/input.js
@@ -63,7 +63,9 @@ export default class Input extends Component {
     hideUnderline: PropTypes.bool,
     value: PropTypes.oneOfType([
       PropTypes.number, PropTypes.string
-    ])
+    ]),
+    min: PropTypes.any,
+    max: PropTypes.any
   };
 
   static defaultProps = {
@@ -86,7 +88,7 @@ export default class Input extends Component {
 
   render () {
     const { value } = this.state;
-    const { children, className, hideUnderline, disabled, error, label, hint, multiLine, rows, type } = this.props;
+    const { children, className, hideUnderline, disabled, error, label, hint, multiLine, rows, type, min, max } = this.props;
 
     const readOnly = this.props.readOnly || disabled;
 
@@ -130,6 +132,8 @@ export default class Input extends Component {
           onChange={ this.onChange }
           onKeyDown={ this.onKeyDown }
           inputStyle={ inputStyle }
+          min={ min }
+          max={ max }
         >
           { children }
         </TextField>
diff --git a/js/src/ui/Form/TypedInput/index.js b/js/src/ui/Form/TypedInput/index.js
new file mode 100644
index 000000000..9c12bf7eb
--- /dev/null
+++ b/js/src/ui/Form/TypedInput/index.js
@@ -0,0 +1,17 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+export default from './typedInput';
diff --git a/js/src/ui/Form/TypedInput/typedInput.css b/js/src/ui/Form/TypedInput/typedInput.css
new file mode 100644
index 000000000..c13206c96
--- /dev/null
+++ b/js/src/ui/Form/TypedInput/typedInput.css
@@ -0,0 +1,31 @@
+/* Copyright 2015, 2016 Ethcore (UK) Ltd.
+/* This file is part of Parity.
+/*
+/* Parity is free software: you can redistribute it and/or modify
+/* it under the terms of the GNU General Public License as published by
+/* the Free Software Foundation, either version 3 of the License, or
+/* (at your option) any later version.
+/*
+/* Parity is distributed in the hope that it will be useful,
+/* but WITHOUT ANY WARRANTY; without even the implied warranty of
+/* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+/* GNU General Public License for more details.
+/*
+/* You should have received a copy of the GNU General Public License
+/* along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+.inputs {
+  padding-top: 2px;
+  overflow-x: hidden;
+
+  label {
+    line-height: 22px;
+    pointer-events: none;
+    color: rgba(255, 255, 255, 0.498039);
+    -webkit-user-select: none;
+    font-size: 12px;
+    top: 11px;
+    position: relative;
+  }
+}
diff --git a/js/src/ui/Form/TypedInput/typedInput.js b/js/src/ui/Form/TypedInput/typedInput.js
new file mode 100644
index 000000000..6bcb5bbf1
--- /dev/null
+++ b/js/src/ui/Form/TypedInput/typedInput.js
@@ -0,0 +1,239 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import React, { Component, PropTypes } from 'react';
+import { MenuItem } from 'material-ui';
+import { range } from 'lodash';
+
+import IconButton from 'material-ui/IconButton';
+import AddIcon from 'material-ui/svg-icons/content/add';
+import RemoveIcon from 'material-ui/svg-icons/content/remove';
+
+import { Input, InputAddressSelect, Select } from '../../../ui';
+import { ABI_TYPES } from '../../../util/abi';
+
+import styles from './typedInput.css';
+
+export default class TypedInput extends Component {
+
+  static propTypes = {
+    onChange: PropTypes.func.isRequired,
+    accounts: PropTypes.object.isRequired,
+    param: PropTypes.object.isRequired,
+
+    error: PropTypes.any,
+    value: PropTypes.any,
+    label: PropTypes.string
+  };
+
+  render () {
+    const { param } = this.props;
+    const { type } = param;
+
+    if (type === ABI_TYPES.ARRAY) {
+      const { accounts, label, value = param.default } = this.props;
+      const { subtype, length } = param;
+
+      const fixedLength = !!length;
+
+      const inputs = range(length || value.length).map((_, index) => {
+        const onChange = (inputValue) => {
+          const newValues = [].concat(this.props.value);
+          newValues[index] = inputValue;
+          this.props.onChange(newValues);
+        };
+
+        return (
+          <TypedInput
+            key={ `${subtype.type}_${index}` }
+            onChange={ onChange }
+            accounts={ accounts }
+            param={ subtype }
+            value={ value[index] }
+          />
+        );
+      });
+
+      return (
+        <div className={ styles.inputs }>
+          <label>{ label }</label>
+          { fixedLength ? null : this.renderLength() }
+          { inputs }
+        </div>
+      );
+    }
+
+    return this.renderType(type);
+  }
+
+  renderLength () {
+    const iconStyle = {
+      width: 16,
+      height: 16
+    };
+
+    const style = {
+      width: 32,
+      height: 32,
+      padding: 0
+    };
+
+    return (
+      <div>
+        <IconButton
+          iconStyle={ iconStyle }
+          style={ style }
+          onClick={ this.onAddField }
+        >
+          <AddIcon />
+        </IconButton>
+
+        <IconButton
+          iconStyle={ iconStyle }
+          style={ style }
+          onClick={ this.onRemoveField }
+        >
+          <RemoveIcon />
+        </IconButton>
+      </div>
+    );
+  }
+
+  renderType (type) {
+    if (type === ABI_TYPES.ADDRESS) {
+      return this.renderAddress();
+    }
+
+    if (type === ABI_TYPES.BOOL) {
+      return this.renderBoolean();
+    }
+
+    if (type === ABI_TYPES.STRING) {
+      return this.renderDefault();
+    }
+
+    if (type === ABI_TYPES.BYTES) {
+      return this.renderDefault();
+    }
+
+    if (type === ABI_TYPES.INT) {
+      return this.renderNumber();
+    }
+
+    if (type === ABI_TYPES.FIXED) {
+      return this.renderNumber();
+    }
+
+    return this.renderDefault();
+  }
+
+  renderNumber () {
+    const { label, value, error, param } = this.props;
+
+    return (
+      <Input
+        label={ label }
+        value={ value }
+        error={ error }
+        onSubmit={ this.onSubmit }
+        type='number'
+        min={ param.signed ? null : 0 }
+      />
+    );
+  }
+
+  renderDefault () {
+    const { label, value, error } = this.props;
+
+    return (
+      <Input
+        label={ label }
+        value={ value }
+        error={ error }
+        onSubmit={ this.onSubmit }
+      />
+    );
+  }
+
+  renderAddress () {
+    const { accounts, label, value, error } = this.props;
+
+    return (
+      <InputAddressSelect
+        accounts={ accounts }
+        label={ label }
+        value={ value }
+        error={ error }
+        onChange={ this.onChange }
+        editing
+      />
+    );
+  }
+
+  renderBoolean () {
+    const { label, value, error } = this.props;
+
+    const boolitems = ['false', 'true'].map((bool) => {
+      return (
+        <MenuItem
+          key={ bool }
+          value={ bool }
+          label={ bool }
+        >
+          { bool }
+        </MenuItem>
+      );
+    });
+
+    return (
+      <Select
+        label={ label }
+        value={ value ? 'true' : 'false' }
+        error={ error }
+        onChange={ this.onChangeBool }
+      >
+        { boolitems }
+      </Select>
+    );
+  }
+
+  onChangeBool = (event, _index, value) => {
+    this.props.onChange(value === 'true');
+  }
+
+  onChange = (event, value) => {
+    this.props.onChange(value);
+  }
+
+  onSubmit = (value) => {
+    this.props.onChange(value);
+  }
+
+  onAddField = () => {
+    const { value, onChange, param } = this.props;
+    const newValues = [].concat(value, param.subtype.default);
+
+    onChange(newValues);
+  }
+
+  onRemoveField = () => {
+    const { value, onChange } = this.props;
+    const newValues = value.slice(0, -1);
+
+    onChange(newValues);
+  }
+
+}
diff --git a/js/src/ui/Form/index.js b/js/src/ui/Form/index.js
index 061cdddd0..46bb106f4 100644
--- a/js/src/ui/Form/index.js
+++ b/js/src/ui/Form/index.js
@@ -16,6 +16,7 @@
 
 import AddressSelect from './AddressSelect';
 import FormWrap from './FormWrap';
+import TypedInput from './TypedInput';
 import Input from './Input';
 import InputAddress from './InputAddress';
 import InputAddressSelect from './InputAddressSelect';
@@ -27,6 +28,7 @@ export default from './form';
 export {
   AddressSelect,
   FormWrap,
+  TypedInput,
   Input,
   InputAddress,
   InputAddressSelect,
diff --git a/js/src/ui/index.js b/js/src/ui/index.js
index ebfce3ad1..69a7d26c3 100644
--- a/js/src/ui/index.js
+++ b/js/src/ui/index.js
@@ -29,7 +29,7 @@ import ContextProvider from './ContextProvider';
 import CopyToClipboard from './CopyToClipboard';
 import Editor from './Editor';
 import Errors from './Errors';
-import Form, { AddressSelect, FormWrap, Input, InputAddress, InputAddressSelect, InputChip, InputInline, Select } from './Form';
+import Form, { AddressSelect, FormWrap, TypedInput, Input, InputAddress, InputAddressSelect, InputChip, InputInline, Select } from './Form';
 import IdentityIcon from './IdentityIcon';
 import IdentityName from './IdentityName';
 import MethodDecoding from './MethodDecoding';
@@ -62,6 +62,7 @@ export {
   Errors,
   Form,
   FormWrap,
+  TypedInput,
   Input,
   InputAddress,
   InputAddressSelect,
diff --git a/js/src/util/abi.js b/js/src/util/abi.js
new file mode 100644
index 000000000..e7947233b
--- /dev/null
+++ b/js/src/util/abi.js
@@ -0,0 +1,146 @@
+// Copyright 2015, 2016 Ethcore (UK) Ltd.
+// This file is part of Parity.
+
+// Parity is free software: you can redistribute it and/or modify
+// it under the terms of the GNU General Public License as published by
+// the Free Software Foundation, either version 3 of the License, or
+// (at your option) any later version.
+
+// Parity is distributed in the hope that it will be useful,
+// but WITHOUT ANY WARRANTY; without even the implied warranty of
+// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+// GNU General Public License for more details.
+
+// You should have received a copy of the GNU General Public License
+// along with Parity.  If not, see <http://www.gnu.org/licenses/>.
+
+import { range } from 'lodash';
+
+const ARRAY_TYPE = 'ARRAY_TYPE';
+const ADDRESS_TYPE = 'ADDRESS_TYPE';
+const STRING_TYPE = 'STRING_TYPE';
+const BOOL_TYPE = 'BOOL_TYPE';
+const BYTES_TYPE = 'BYTES_TYPE';
+const INT_TYPE = 'INT_TYPE';
+const FIXED_TYPE = 'FIXED_TYPE';
+
+export const ABI_TYPES = {
+  ARRAY: ARRAY_TYPE, ADDRESS: ADDRESS_TYPE,
+  STRING: STRING_TYPE, BOOL: BOOL_TYPE,
+  BYTES: BYTES_TYPE, INT: INT_TYPE,
+  FIXED: FIXED_TYPE
+};
+
+export function parseAbiType (type) {
+  const arrayRegex = /^(.+)\[(\d*)]$/;
+
+  if (arrayRegex.test(type)) {
+    const matches = arrayRegex.exec(type);
+
+    const subtype = parseAbiType(matches[1]);
+    const M = parseInt(matches[2]) || null;
+    const defaultValue = !M
+      ? []
+      : range(M).map(() => subtype.default);
+
+    return {
+      type: ARRAY_TYPE,
+      subtype: subtype,
+      length: M,
+      default: defaultValue
+    };
+  }
+
+  const lengthRegex = /^(u?int|bytes)(\d{1,3})$/;
+
+  if (lengthRegex.test(type)) {
+    const matches = lengthRegex.exec(type);
+
+    const subtype = parseAbiType(matches[1]);
+    const length = parseInt(matches[2]);
+
+    return {
+      ...subtype,
+      length
+    };
+  }
+
+  const fixedLengthRegex = /^(u?fixed)(\d{1,3})x(\d{1,3})$/;
+
+  if (fixedLengthRegex.test(type)) {
+    const matches = fixedLengthRegex.exec(type);
+
+    const subtype = parseAbiType(matches[1]);
+    const M = parseInt(matches[2]);
+    const N = parseInt(matches[3]);
+
+    return {
+      ...subtype,
+      M, N
+    };
+  }
+
+  if (type === 'string') {
+    return {
+      type: STRING_TYPE,
+      default: ''
+    };
+  }
+
+  if (type === 'bool') {
+    return {
+      type: BOOL_TYPE,
+      default: false
+    };
+  }
+
+  if (type === 'address') {
+    return {
+      type: ADDRESS_TYPE,
+      default: ''
+    };
+  }
+
+  if (type === 'bytes') {
+    return {
+      type: BYTES_TYPE,
+      default: '0x'
+    };
+  }
+
+  if (type === 'uint') {
+    return {
+      type: INT_TYPE,
+      default: 0,
+      length: 256,
+      signed: false
+    };
+  }
+
+  if (type === 'int') {
+    return {
+      type: INT_TYPE,
+      default: 0,
+      length: 256,
+      signed: true
+    };
+  }
+
+  if (type === 'ufixed') {
+    return {
+      type: FIXED_TYPE,
+      default: 0,
+      length: 256,
+      signed: false
+    };
+  }
+
+  if (type === 'fixed') {
+    return {
+      type: FIXED_TYPE,
+      default: 0,
+      length: 256,
+      signed: true
+    };
+  }
+}