diff --git a/src/convert.rs b/src/convert.rs
new file mode 100644
index 0000000..1bff384
--- /dev/null
+++ b/src/convert.rs
@@ -0,0 +1,391 @@
+use serde_json::Value;
+use std::collections::HashMap;
+use std::str::FromStr;
+
+use crate::error::{ConfigForgeError, Result};
+
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ConfigFormat {
+    Json,
+    Yaml,
+    Toml,
+    Env,
+    Ini,
+}
+
+impl FromStr for ConfigFormat {
+    type Err = ConfigForgeError;
+
+    fn from_str(s: &str) -> Result<Self> {
+        match s.to_lowercase().as_str() {
+            "json" => Ok(ConfigFormat::Json),
+            "yaml" | "yml" => Ok(ConfigFormat::Yaml),
+            "toml" => Ok(ConfigFormat::Toml),
+            "env" | "dotenv" => Ok(ConfigFormat::Env),
+            "ini" => Ok(ConfigFormat::Ini),
+            _ => Err(ConfigForgeError::UnsupportedFormat {
+                format: s.to_string(),
+            }),
+        }
+    }
+}
+
+impl std::fmt::Display for ConfigFormat {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            ConfigFormat::Json => write!(f, "json"),
+            ConfigFormat::Yaml => write!(f, "yaml"),
+            ConfigFormat::Toml => write!(f, "toml"),
+            ConfigFormat::Env => write!(f, "env"),
+            ConfigFormat::Ini => write!(f, "ini"),
+        }
+    }
+}
+
+pub fn detect_format(path: &str) -> ConfigFormat {
+    let ext = path.split('.').last().unwrap_or("").to_lowercase();
+    match ext.as_str() {
+        "json" => ConfigFormat::Json,
+        "yaml" | "yml" => ConfigFormat::Yaml,
+        "toml" => ConfigFormat::Toml,
+        "env" | "dotenv" => ConfigFormat::Env,
+        "ini" | "cfg" | "conf" => ConfigFormat::Ini,
+        _ => ConfigFormat::Json,
+    }
+}
+
+pub fn detect_format_from_content(content: &str) -> Result<ConfigFormat> {
+    let trimmed = content.trim_start();
+    if trimmed.starts_with('{') || trimmed.starts_with('[') {
+        return Ok(ConfigFormat::Json);
+    }
+    if trimmed.starts_with('#') || trimmed.starts_with("---") || trimmed.contains(": ") && !trimmed.contains("= ") {
+        return Ok(ConfigFormat::Yaml);
+    }
+    if trimmed.contains('=') && !trimmed.contains(" = ") && !trimmed.starts_with('[') {
+        return Ok(ConfigFormat::Env);
+    }
+    if trimmed.starts_with('[') {
+        return Ok(ConfigFormat::Ini);
+    }
+    if trimmed.contains(" = ") {
+        return Ok(ConfigFormat::Toml);
+    }
+    Ok(ConfigFormat::Json)
+}
+
+pub fn parse_content(content: &str, format: ConfigFormat) -> Result<Value> {
+    match format {
+        ConfigFormat::Json => parse_json(content),
+        ConfigFormat::Yaml => parse_yaml(content),
+        ConfigFormat::Toml => parse_toml(content),
+        ConfigFormat::Env => parse_env(content),
+        ConfigFormat::Ini => parse_ini(content),
+    }
+}
+
+fn parse_json(content: &str) -> Result<Value> {
+    serde_json::from_str(content).map_err(|e| ConfigForgeError::ParseError {
+        format: "JSON".to_string(),
+        details: e.to_string(),
+    })
+}
+
+fn parse_yaml(content: &str) -> Result<Value> {
+    serde_yaml::from_str(content).map_err(|e| ConfigForgeError::ParseError {
+        format: "YAML".to_string(),
+        details: e.to_string(),
+    })
+}
+
+fn parse_toml(content: &str) -> Result<Value> {
+    let value: toml::Value = toml::from_str(content).map_err(|e| ConfigForgeError::ParseError {
+        format: "TOML".to_string(),
+        details: e.to_string(),
+    })?;
+    Ok(toml_to_value(value))
+}
+
+fn toml_to_value(value: toml::Value) -> Value {
+    match value {
+        toml::Value::String(s) => Value::String(s),
+        toml::Value::Integer(i) => Value::Number(serde_json::Number::from(i)),
+        toml::Value::Float(f) => {
+            if let Some(n) = serde_json::Number::from_f64(f) {
+                Value::Number(n)
+            } else {
+                Value::Null
+            }
+        }
+        toml::Value::Boolean(b) => Value::Bool(b),
+        toml::Value::Datetime(dt) => Value::String(dt.to_string()),
+        toml::Value::Array(arr) => Value::Array(arr.into_iter().map(toml_to_value).collect()),
+        toml::Value::Table(table) => {
+            let mut map = serde_json::Map::new();
+            for (k, v) in table {
+                map.insert(k, toml_to_value(v));
+            }
+            Value::Object(map)
+        }
+    }
+}
+
+fn parse_env(content: &str) -> Result<Value> {
+    let mut map = serde_json::Map::new();
+    for line in content.lines() {
+        let line = line.trim();
+        if line.is_empty() || line.starts_with('#') {
+            continue;
+        }
+        if let Some(eq_idx) = line.find('=') {
+            let key = line[..eq_idx].trim().to_string();
+            let value = line[eq_idx + 1..].trim().to_string();
+            let value = value.trim_matches('"').trim_matches('\'').to_string();
+            map.insert(key, Value::String(value));
+        }
+    }
+    Ok(Value::Object(map))
+}
+
+fn parse_ini(content: &str) -> Result<Value> {
+    let ini = ini::Ini::load_from_str(content).map_err(|e| ConfigForgeError::ParseError {
+        format: "INI".to_string(),
+        details: e.to_string(),
+    })?;
+    let mut map = serde_json::Map::new();
+    for (section, prop) in ini.iter() {
+        let mut section_map = serde_json::Map::new();
+        if let Some(section_name) = section {
+            for (k, v) in prop.iter() {
+                section_map.insert(k.clone(), Value::String(v.clone().unwrap_or_default()));
+            }
+            map.insert(section_name.clone(), Value::Object(section_map));
+        } else {
+            for (k, v) in prop.iter() {
+                map.insert(k.clone(), Value::String(v.clone().unwrap_or_default()));
+            }
+        }
+    }
+    Ok(Value::Object(map))
+}
+
+pub fn convert(value: Value, to_format: ConfigFormat) -> Result<String> {
+    match to_format {
+        ConfigFormat::Json => to_json(&value),
+        ConfigFormat::Yaml => to_yaml(&value),
+        ConfigFormat::Toml => to_toml(&value),
+        ConfigFormat::Env => to_env(&value),
+        ConfigFormat::Ini => to_ini(&value),
+    }
+}
+
+fn to_json(value: &Value) -> Result<String> {
+    serde_json::to_string_pretty(value).map_err(|e| ConfigForgeError::ConversionError {
+        details: e.to_string(),
+    })
+}
+
+fn to_yaml(value: &Value) -> Result<String> {
+    serde_yaml::to_string(value).map_err(|e| ConfigForgeError::ConversionError {
+        details: e.to_string(),
+    })
+}
+
+fn to_toml(value: &Value) -> Result<String> {
+    let toml_value = value_to_toml(value)?;
+    toml::to_string_pretty(&toml_value).map_err(|e| ConfigForgeError::ConversionError {
+        details: e.to_string(),
+    })
+}
+
+fn value_to_toml(value: &Value) -> Result<toml::Value> {
+    match value {
+        Value::String(s) => Ok(toml::Value::String(s.clone())),
+        Value::Number(n) => {
+            if let Some(i) = n.as_i64() {
+                Ok(toml::Value::Integer(i))
+            } else if let Some(f) = n.as_f64() {
+                Ok(toml::Value::Float(f))
+            } else {
+                Ok(toml::Value::String(n.to_string()))
+            }
+        }
+        Value::Bool(b) => Ok(toml::Value::Boolean(*b)),
+        Value::Null => Ok(toml::Value::String(String::new())),
+        Value::Array(arr) => {
+            let converted: Result<Vec<toml::Value>> = arr.iter().map(value_to_toml).collect();
+            Ok(toml::Value::Array(converted?))
+        }
+        Value::Object(map) => {
+            let mut table = toml::Map::new();
+            for (k, v) in map {
+                table.insert(k.clone(), value_to_toml(v)?);
+            }
+            Ok(toml::Value::Table(table))
+        }
+    }
+}
+
+fn to_env(value: &Value) -> Result<String> {
+    match value {
+        Value::Object(map) => {
+            let mut lines = Vec::new();
+            for (k, v) in map {
+                let env_value = match v {
+                    Value::String(s) => s.clone(),
+                    Value::Number(n) => n.to_string(),
+                    Value::Bool(b) => b.to_string(),
+                    Value::Null => String::new(),
+                    _ => serde_json::to_string(v).unwrap_or_default(),
+                };
+                lines.push(format!("{}={}", k.to_uppercase(), env_value));
+            }
+            Ok(lines.join("\n"))
+        }
+        _ => Err(ConfigForgeError::ConversionError {
+            details: "ENV format requires an object at root".to_string(),
+        })
+    }
+}
+
+fn to_ini(value: &Value) -> Result<String> {
+    let mut output = String::new();
+    match value {
+        Value::Object(map) => {
+            let mut has_global = false;
+            for (k, v) in map {
+                if let Value::Object(section) = v {
+                    output.push('[');
+                    output.push_str(k);
+                    output.push_str("]\n");
+                    for (key, val) in section {
+                        output.push_str(key);
+                        output.push_str(" = ");
+                        if let Value::String(s) = val {
+                            output.push_str(s);
+                        } else {
+                            output.push_str(&val.to_string());
+                        }
+                        output.push('\n');
+                    }
+                    output.push('\n');
+                } else {
+                    has_global = true;
+                    output.push_str(k);
+                    output.push_str(" = ");
+                    if let Value::String(s) = v {
+                        output.push_str(s);
+                    } else {
+                        output.push_str(&v.to_string());
+                    }
+                    output.push('\n');
+                }
+            }
+            if has_global {
+                output.push('\n');
+            }
+            Ok(output)
+        }
+        _ => Err(ConfigForgeError::ConversionError {
+            details: "INI format requires an object at root".to_string(),
+        })
+    }
+}
+
+pub fn read_file(path: &std::path::Path) -> Result<String> {
+    std::fs::read_to_string(path).map_err(|_| ConfigForgeError::FileNotFound {
+        path: path.to_string_lossy().to_string(),
+    })
+}
+
+pub fn write_file(path: &std::path::Path, content: &str) -> Result<()> {
+    if let Some(parent) = path.parent() {
+        std::fs::create_dir_all(parent)?;
+    }
+    std::fs::write(path, content)?;
+    Ok(())
+}
+
+pub fn infer_schema(value: &Value) -> Value {
+    match value {
+        Value::Null => json!({"type": "null"}),
+        Value::Bool(_) => json!({"type": "boolean"}),
+        Value::Number(n) => {
+            if n.is_i64() {
+                json!({"type": "integer"})
+            } else if n.is_f64() {
+                json!({"type": "number"})
+            } else {
+                json!({"type": "number"})
+            }
+        }
+        Value::String(s) => {
+            if s.starts_with('/') && s.ends_with('/') {
+                json!({"type": "string", "format": "regex"})
+            } else if s.contains('@') {
+                json!({"type": "string", "format": "email"})
+            } else {
+                json!({"type": "string"})
+            }
+        }
+        Value::Array(arr) => {
+            if arr.is_empty() {
+                json!({"type": "array", "items": {}})
+            } else {
+                let mut types = std::collections::HashSet::new();
+                let mut items = serde_json::Map::new();
+                for item in arr {
+                    let item_schema = infer_schema(item);
+                    if let Some(type_) = item_schema.get("type") {
+                        types.insert(type_.clone());
+                    }
+                    for (k, v) in item_schema.as_object().unwrap_or(&serde_json::Map::new()) {
+                        if let Some(existing) = items.get(k) {
+                            if existing != v {
+                                items.remove(k);
+                            }
+                        } else {
+                            items.insert(k.clone(), v.clone());
+                        }
+                    }
+                }
+                let mut result = serde_json::Map::new();
+                result.insert("type".to_string(), json!("array"));
+                if !types.is_empty() && types.len() == 1 {
+                    result.insert("items".to_string(), json!({"type": types.iter().next().unwrap()}));
+                } else {
+                    let mut any_of = Vec::new();
+                    for type_ in types {
+                        any_of.push(json!({"type": type_}));
+                    }
+                    if !any_of.is_empty() {
+                        result.insert("items".to_string(), json!({"anyOf": any_of}));
+                    } else {
+                        result.insert("items".to_string(), json!({}));
+                    }
+                }
+                Value::Object(result)
+            }
+        }
+        Value::Object(map) => {
+            let mut properties = serde_json::Map::new();
+            let mut required = Vec::new();
+
+            for (k, v) in map {
+                properties.insert(k.clone(), infer_schema(v));
+                if k.starts_with('_') || k.ends_with('?') || k.starts_with("optional_") {
+                } else {
+                    required.push(k.clone());
+                }
+            }
+
+            let mut result = serde_json::Map::new();
+            result.insert("type".to_string(), json!("object"));
+            result.insert("properties".to_string(), Value::Object(properties));
+            if !required.is_empty() {
+                result.insert("required".to_string(), json!(required));
+            }
+            Value::Object(result)
+        }
+    }
+}